EFFECT OF HORN (SONOTRODE) PROFILE ON WELD

Transcription

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EFFECT OF HORN (SONOTRODE) PROFILE ON
WELD STRENGTH OF HDPE PLASTIC WELD BY
USING ULTRASONIC WELDING
RAVI K. PATEL
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(ENROLLMENT NO: 12014051012)
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DEPARTMENT OF MECHANICAL ENGINEERING
U. V. PATEL COLLEGE OF ENGINEERING
GANPAT UNIVERSITY
KHERVA, MEHSANA- 384012
APRIL-2014
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EFFECT OF HORN (SONOTRODE) PROFILE ON
WELD STRENGTH OF HDPE PLASTIC WELD BY
USING ULTRASONIC WELDING
A DISSERTATION SUBMITTED TO
GANPAT UNIVERSITY
IN PARTIAL FULFILLMENT OF THE REQUIREMENT FOR THE
DEGREE OF
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MASTER OF TECHNOLOGY
IN
MECHANICAL ENGINEERING
WITH SPECIALIZATION IN
Advanced Manufacturing Techniques (AMT)
SUBMITTED BY
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RAVI K. PATEL
(ENROLLMENT NO: 12014051012)
UNDER THE GUIDANCE OF
Prof. C. P. PATEL
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APRIL-2014
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DEPARTMENT OF MECHANICAL ENGINEERING
GANPAT UNIVERSITY
KHERVA, MEHSANA- 384012
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Department of Mechanical
Engineering
U. V. Patel College of Engineering
Ganpat University
Kherva- 384012
Certificate
This is to certify that the work presented in the Dissertation
Entitled
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EFFECT OF HORN (SONOTRODE) PROFILE ON WELD STRENGTH
OF HDPE PLASTIC WELD BY USING ULTRASONIC WELDING
Has been carried out by
RAVI K. PATEL
(Enrollment No: 12014051012)
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In a manner sufficiently satisfactory to warrant its acceptances a partial fulfillment of the
requirement for the award of the Degree of
MASTER OF TECHNOLOGY
In
MECHANICAL ENGINEERING
With Specialization In
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Advanced Manufacturing Techniques (AMT)
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This is a bonafide work done by the student and has not been submitted to any other
University/Institute for the award of any other Degree.
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Prof. C. P. Patel
Guide,
Associate professor,
Mechanical Engineering Department.
Prof. V. B. Patel
Associate Professor and Head of
Department,
Mechanical Engineering Department.
Dr. P. H. SHAH
Principal,
U.V. Patel College of Engineering,
Ganpat University Kherva, Mehsana.
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Department of Mechanical Engineering
U. V. Patel College of Engineering
Ganpat University
Kherva- 384012
Certificate of Examination
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This is to certify that we have examined the thesis entitled “Effect
of Horn (sonotrode) profile on weld strength of HDPE plastic weld by Using
Ultrasonic Welding” submitted by Mr. Ravi K. Patel (12014051012), a
postgraduate student of Mechanical Engineering with specialization in
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Advanced Manufacturing Techniques (AMT). We hereby accord our approval
of it as a study carried out and presented in manner required for its acceptance
in partial fulfillment for the Post Graduate Degree for which it has been
submitted. This approval does not necessarily endorse or accept every statement
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made, opinion expressed or conclusion drawn as recorded in this thesis. It only
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signifies the acceptance of the thesis for the purpose for which it is submitted.
Internal Examiner
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External Examiner
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APPROVAL SHEET
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This dissertation is entitled as “EFFECT OF HORN (SONOTRODE) PROFILE
ON WELD STRENGTH OF HDPE PLASTIC WELD BY USING ULTRASONIC
WELDING”, By Ravi K. Patel (12014051012) is approved for the degree of Master of
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Technology in Advanced Manufacturing Techniques (AMT).
Date :
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Place :
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Examiner
Supervisor
Head of department
DECLARATION OF ORIGINALITY
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I hereby certify that I am the sole author of this thesis and that neither any part of
this thesis nor the whole of the thesis has been submitted for a degree to any other
University or Institution.
I certify that, to the best of my knowledge, my thesis does not infringe upon
anyone’s copyright nor violate any proprietary rights and that any ideas, techniques,
quotations, or any other material from the work of other people included in my thesis,
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published or otherwise, are fully acknowledged in accordance with the standard referencing
practices.
I declare that this is a true copy of my thesis, including any final revisions, as
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approved by my thesis review committee.
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Ravi K. Patel
(Enrollment No.: 12014051012)
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Date :
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ACKNOWLEDGEMENT
It is indeed a pleasure for me to express my sincere gratitude to those who have always
helped me for this dissertation work.
First and foremost let me grateful to almighty God. My deepest regards and greatest
admiration remain to my parents, & my brother, who has taught me how to walk on an
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untraded path in the quest of knowledge.
I sincerely convey my gratitude to my guide Prof. C. P. Patel, Mechanical Engineering
Department, UVPCE, Kherva, who made me believe in myself and guided me through the
whole process of dissertation writing. He has never failed to help me to get a grasp on the
subject.
My sincere thanks to Prof. V. B. Patel, Head of Mechanical/Mechatronics Engineering
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Department, and Dr. D. M. Patel and Prof. H. A. Patel, PG Coordinator, Department of
Mechanical/Mechatronics Engineering, Who helped me in pointing the need of the project,
suggestions and encouragement during the project. I am also thankful to Prof.J.P.Patel,
Dr. B.P.Patel, and Prof. J.R.Mevada for their valuable co operation.
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I greatly thankful to Prof. A. B. Pandey, Mechanical Engineering Department, M.S.U.
Baroda, who helped me in my any difficulty in subject and thanks to M.S.university, Baroda
for providing experiment setup.
In addition, I would like to thank all non-teaching staff of Mechanical Engineering
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Department, UVPCE, Kherva, who supported me by providing required materials for my
research work. I would also like to show my gratitude to my friends and colleagues for their
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help and moral support.
Ravi K. Patel
12014051012
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ABSTRACT
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Many of industrial applications and production technologies are based on the application of
ultrasound. In many cases, the phenomenon of ultrasound is also applied in technological
processes of the welding of materials. The main element of equipments that use the effects
of ultrasound for welding is the ultrasonic horn –so called sonotrode. The performance of
ultrasonic equipment, respectively ultrasonic welding technologies depends on properly
designed of sonotrode shape. For proper concentration of ultrasonic energy across work
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piece surface during welding, geometry of horn plays a vital role. In welding, welding
strength like tensile and shear strength also important factor. The different type of horns is
used in ultrasonic welding. A horn profile is directly affected to welding strength. In
ultrasonic welding parameters like pressure, Amplitude, thickness, time also affected to the
strength.
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This dissertation work, discusses on design of different shaped acoustic horns like conical,
stepped and exponential made from EN24 material for ultrasonic welding of HDPE (HighDensity Polyethylene) plastics. First, the theoretical dimensions of different shaped horn are
calculated and compared with the dimensions obtained through commercial horn design
software CARD®. Using this type of horn profile test run on HDPE plastic. Then testing the
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weld tensile strength of HDPE sample with different welding parameter (pressure,
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Amplitude, thickness) with respect to different hone profile in ultrasonic welding.
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Table of Content
Page No
Title
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Sr No
I
Certificate
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Certificate of Examination
III
Approval sheet
IV
Declaration of originality
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Acknowledgements
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VI
Abstract
VII
Table of Contents
VIII
List of Figure
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IX
List of Table
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Introduction
1
1.1 What is ultrasonic?
1
1.2 Ultrasonic machine components
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Chapter 1
Nomenclature
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1.2.1 Generator
2
1.2.2 Transducer
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1.2.3 Piezoelectric crystal
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1.2.4 Piezoelectric ceramic
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1.2.6 Sonotrode (horn)
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1.2.5 Magnetostrictive transducers
1.3 Concept of ultrasonic plastic welding
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1.4 Process principal
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1.5 Principles of Ultrasonic Metal Welding (USMW)
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1.7 Important parameters of the welding process
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1.8 Special characteristics of ultrasonic metal welding
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1.9 Plastic Welding Vs Metal Welding
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1.6 Ultrasonic Metal Welding (USMW)
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1.12.1 Cleaning
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1.12.2 Machining
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1.12.3 Soldering and welding
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1.11 Disadvantages of ultrasonic processes
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1.12 Application of ultrasonic
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1.10 Advantages of ultrasonic welding processes
1.12.4 Electronics
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1.13 Application of ultrasonic plastic welding
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1.14 Theoretical background
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1.14.1 Physics of ultrasonic
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1.14.2 Ultrasonic wave’s types
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1.14.3 Longitudinal waves
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1.14.5 Surface waves
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1.14.6 Wave Generation
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1.14.4 Shear wave
1.14.7 Propagation of Elastic Waves in Solids
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Literature review
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Chapter 3
Design & manufacturing of horn (sonotrode)
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3.1 Introduction
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Chapter 2
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3.3 Theoretical Design of Sonotrode
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3.3.1 Exponential Profile
3.3.2 Conical Profile
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3.3.3 Step-Cylindrical Profile
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3.2 Selection of material
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3.4.1 Overview of CARD
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3.4.2. Limitations
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3.4 Design using CARD software
3.5 Manufacturing of horn
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3.5.1 Program generated by NX8
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Chapter 4
33
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Design of Experiment
48
4.1 Introduction
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4.2 Methods of DOE
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4.3 Selection of parameters &experiment plan
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4.5 Output parameters
Experiment set-up
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5.1 Specification of ultrasonic welding machine
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5.2 Generator controller
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Chapter 6
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5.3 Transducer and concentrator
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5.4 air compressor, fixture and tensile testing machine
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Result and discussion
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6.1 Comparison of design results with CARD output
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Chapter 5
4.4 Input parameters
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6.2.1.2 Thickness ratio
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6.2 Tensile strength VS. Pressure & Thickness ratio
6.2.1 Discussion
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6.2.1.1 Pressure
6.3 Comparison of different horn value
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6.3.1 Discussion
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6.4 Problem face in step-cylindrical design
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Conclusion
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Chapter 8
Future scope
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Chapter 9
References
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Chapter 7
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List of Figures
Title
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Figure No.
1.1
Ultrasonic plastic welding machines
1.2
Schematic of USW system
1.3
Sonotrode
1.4
Ultrasonic plastic welding principal
1.5
Schematic of the ultrasonic bonding region
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1.6
Schematic of USMW system
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1.7
(a) Longitudinal Wave
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Schematic of a free vibration of a non-uniform bar
3.2
Stress diagram for conical shaped sonotrode profile
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3.3
CARD result for conical shaped sonotrode profile
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3.4
Stress diagram for step-cylindrical shaped sonotrode profile
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3.5
CARD result for step-cylindrical shaped sonotrode profile
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Stress diagram for Exponential shaped sonotrode profile
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CARD result for Exponential shaped sonotrode profile
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(a) conical horn
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(b) Step-cylindrical horn
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(c) Exponential horn
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3.9
Model in solid works
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5.1
Machine setup in Laboratory
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5.2
Generator controller
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5.3
Transducer and concentrator with tool holder and tool
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3.6
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(b) Shear Wave
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3.8
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Air compressors
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5.5
Fixture
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5.6
Tensile testing machine
5.7
Samples of conical horn before testing
5.8
Samples of step-cylindrical horn before testing
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5.9
Samples of exponential horn before testing
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5.10
Samples of conical horn after testing
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5.11
Samples of step-cylindrical horn after testing
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5.12
Samples of exponential horn after testing
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6.1
Graph of Tensile Strength Vs. Thickness ratio & pressure
For Sample Prepared By Conical Horn
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6.2
Graph of Tensile Strength Vs. Thickness ratio & pressure
For Sample Prepared By Step-Cylindrical Horn
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6.3
Graph of Tensile Strength Vs. Thickness ratio & Pressure
For Sample Prepared By Exponential Horn
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6.4
Graph of Tensile Strength Vs. Thickness ratio & Pressure of
three Different Horn
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Stress diagram for step-cylindrical shaped sonotrode profile
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CARD result for step-cylindrical shaped sonotrode profile
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6.6
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6.5
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5.4
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List of Table
Title
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3.1
Properties of EN24
3.2
Typical input parameter of CARD
3.3
Values of Different shaped Horn
4.1
Factor with levels value
4.2
Experiment Runs
5.2
Properties of HDPE
5.3
Sample number and values
6.1
Tensile Testing Results of 9 Samples
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Table No.
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Nomenclature
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Description
Transformation ratio
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Symbol
Cross-sectional area at larger end of sonotrode
A2
Cross-sectional area at smaller end of sonotrode
Velocity of sound in the material
d1
Diameter at larger end of sonotrode
d2
Diameter at smaller end of sonotrode
E
Young’s modulus
f
Frequency of vibration
G
Shear modulus
g
L
L1
Acceleration due to gravity
Resonance length of sonotrode
Length of step-1 of sonotrode
Length of step-2 of sonotrode
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A1
Taper ascent of Exponential sonotrode
T
Time period of vibration
v1
Amplitude larger end of sonotrode
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Amplitude at smaller end of sonotrode
vx
Displacement of the section x of sonotrode
α
Ascent of taper for conical sonotrode
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λ
Wavelength
μ
Poisson’s ratio
ρ
Mass density of sonotrode material
σx
Stress level on the section x of area A
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INTRODUCTION
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CHAPTER-1
Figure: 1.1 ultrasonic plastic welding machines [7]
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1.1 What is Ultrasonic?
Ultrasonic is acoustic (sound) energy in the form of waves having a frequency above the
human hearing range. The highest frequency that the human ear can detect is approximately
20 thousand cycles per second (20,000 Hz). This is where the sonic range ends, and where
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the ultrasonic range begins. Ultrasound is used in electronic, navigational, industrial, and
security applications. It is also used in medicine to view internal organs of the body.
Ultrasonic is a branch of acoustics dealing with the generation and use of (generally)
inaudible acoustic waves. There are two broad areas of use, sometimes called as the low-and
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high-intensity applications. In low-intensity applications, the intent is to convey information
about or through a system, while in high-intensity applications, the intent is to permanently
alter a system. To some extent, the low- and high-intensity fields are also delineated by a
frequency range and power level. Thus, low-intensity applications typically involve
frequencies on the order of 10 Hz or higher and power levels on the order of mille watts.
High-intensity applications will typically involve frequencies of 5 to 100 kHz and powers of
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hundreds to thousands of watts. In actual fact, the total frequency range of all ultrasonic
applications is enormous, ranging from 5 - 10 kHz to as high as 10 GHz. There are also
applications, such as sonar, which are exceptions to the previous categorizations, since
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1.2 Ultrasonic machine components
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intense power levels are involved in conveying information via underwater sound. [1, 2]
Figure: 1.2 Schematic of USW system [21]
1.2.1 Generator
It converts frequency of 50/60 Hz, available at the mains to the frequency ultrasonic range,
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say 20000 Hz or more. The main requirements of generator used in ultrasonic welding
applications are,
Stable frequency which can be evenly regulated over a range,

Controlled output over a range,

Higher harmonic should not present in the output voltage curve,
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
The significance of third requirement lines in the fact that if high harmonics are present in
addition to the fundamental, additional electric power losses will result, not only in
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generator itself, but in transducer also. A general requirement is that they should be
compact, reliable in operation, and be simple to operate.
The generator may be an electrical machine or some form of thermionic valve source. High
frequency alternators are multi-pole machines with variable speed control for frequency
adjustment. Valve generator, which may be independently or self excited, have found favor
because they can be designed for any desired output and with wide range of frequency
control.
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It also has facility to tune the frequency over a narrow range i.e. slight variation in
frequency is possible; since tool wear and other variables may result in generator not being
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matched, the small change in resonant frequency is needed. [23]
1.2.2 Transducer
The transducers are a heart of USW. It converts the available high frequency electrical
energy into the mechanical energy i.e. in the form of oscillation of transducer material.
There are basically three types of transducers which are widely used in ultra sonic welding
1.2.3 Piezoelectric crystal
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which are described below. [23]
It works on piezoelectric effect. Piezoelectric effect was first discovered by Curie brothers
in 1880, occurs in crystals having one or more polar axis or the absence of centre of
symmetry. Let a slab or a disc of such a crystal is cut with its parallel surfaces laying normal
to a polar axis. On subjecting these slabs to a mechanical stresses, equal and opposite
electric charges appears on the parallel surfaces. Provided that the crystal is not strained
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beyond its elastic limits, the magnitude of charge density is directly proportional to applied
stresses. Curie discovered the converse effect in 1881 ‘when an electric field is applied in
direction of polar axis the slab is mechanically strained and the amount of strain is being
proportional to the intensity of the applied field’. This effect is prominent in crystals such
as quartz, Rochelle salt, tourmaline and lithium-sulphate. The quartz crystal is having
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exceptional chemical and physical stability.
When an alternating voltage of frequency (f) is applied across the faces, small amplitude
oscillation of crystal occurs. The amplitude is increased considerably when f coincides with
one of the natural frequency of mechanical vibration. The natural frequency of mechanical
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vibration varies inversely with the dimension along which they occur; lower frequencies are
produced by ‘length’ vibration and higher with ‘thickness’ vibrations.
Because piezo electric effect can occur only when opposite charges appeared on the
electrode, only odd harmonic can be generated. When crystal is excited at
harmonic, its
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thickness is divided into n equal parts with compression and expansion taking place in
adjoining sections. Where n is even, compression occurs in n/2 of the sections and
expansion occurs in remaining sections; thus there is no strain the crystal. Where n is odd,
(n-1)/2 compression neutralize the same no. of expansion, living either a compression or an
expansion in the remaining section.
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Piezoelectric transducer converts alternating electrical energy directly to mechanical energy
through use of piezoelectric effect. Electrical energy at the ultrasonic frequency is supplied
to the transducer by the ultrasonic generator. This electrical energy is applied to
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piezoelectric element(s) in the transducer, which vibrate. These vibrations are amplified by
the resonant masses of the transducer and directed into the liquid through the radiating plate.
Early piezoelectric transducers utilized such piezoelectric materials as naturally occurring
quartz crystal and barium titanate, which were fragile and unstable. Early piezoelectric
transducers were, therefore, unreliable. Today’s transducers incorporate stronger, more
efficient and highly stable ceramic piezoelectric materials which were develops as a result
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of the efforts of US Navy and its research to develop advance sonar transducers in the
1940’s.
The vast majority of transducer used today for ultrasonic cleaning utilizes the piezoelectric
effect. Piezoelectric transducer has high frequency of compression, low power handling
capacity, and driving voltages are also low. This generally fined application in the field of
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measurement, diagnosis, cleaning etc. [23]
1.2.4 Piezoelectric ceramic
Electrostrictive effect is prominent in all dielectrics, is a phenomenon analogous to
magnetostriction. For most of the materials it is negligible but in certain dielectrics, called
ferroelectrics, the effect is strongly pronounced. The application of electric field in given
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direction produced a mechanical strain, the magnitude of which is proportional to the square
of the applied field strength and thus independent of the sense of the applied filed. Thus a
positive strain may occur for both positive and negative values of the exciting field.
After polarization ferroelectric transducer appears to display the same effect as piezoelectric
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crystals transducers and, for this reason it is commonly referred to as being ‘piezoelectric’.
At present, barium titanate, lead meta-niobate and zirconate titanate are the substances most
widely used for Electrostrictive applications. For the construction of this type of transducer
many small crystallites of ferromagnetic material along with suitable additives are bonded
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together to form a ceramic of the required shape. Because these materials are
polycrystalline, they have the advantage over naturally occurring piezoelectric crystals in
that these are isotropic in nature and do not have to be cut along specified axes. Thus it is
possible to produce a concave transducer shape so that ultrasonic radiation can be focused
without use of an auxiliary lens system.
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This has moderate power handling capacities, moderate driving frequency along with high
voltages. It finds wide application for welding plastics and soft brittle materials. [23]
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1.2.5 Magnetostrictive transducers
It works on Megnetostrictive effect. This effect occurs with ferromagnetic material and
certain non-metals called ferrites. The magnetostrictive effect was discovered by joule in
1847 and converse effect by villari in 1868. When a rod or bar of ferromagnetic or
ferrimegnetic material is subjected to a magnetic field a mechanical stress applied to a rod
or bar, it experiences a change in length. Conversely, mechanical stress applied to a rod or
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bar causes a change in intensity of magnetization. This effect is prominent for the materials
like cobalt, nickel and iron. Whether there is increase or decrease in length depend entirely
on the nature of the material and on the strength of the applied magnetic field. The change
in length is independent of the direction of the field. Thus, when alternate expansion and
contraction.
These are generally used in high power applications; thus transducer should have
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electromechanical coupling coefficient. However, much energy is dissipated in the form of
heat due to hysteresis and the induction of the eddy current; the transducer material should
have a narrow hysteresis loop and a high electrical resistivity. Some cooling device is
necessary to keep temperature below Curie point. Using laminated stacks can minimize
Eddy current losses. Window type and ring type transducers are commonly used. This is
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much suitable for cutting operations. It has high power handling capacities, moderate
frequencies and driving voltages. [23]
1.2.6 Sonotrode (horn)
The A sonotrode (also referred as concentrator velocity transformer or horn) is the element
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of the ultrasonic machine that supplied energy to the component being welded. Some typical
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commercially available sonotrode are shown in figure 1.3
Figure: 1.3 Sonotrode [22]
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Design of the sonotrode is critical to successful application of ultrasonic energy. It is
designed to resonate at the frequency of the ultrasonic system. When it vibrates, it stretches
and shrinks in length by a small amount. This motion is referred to as the amplitude of the
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sonotrode. Amplitude is measured as the peak-to-peak motion at the face of the sonotrode.
Increasing the voltage to the transducer or changing the booster or the geometry of the
sonotrode can change this value.
Sonotrode are required to bridge the gap between the converter and the work or point of
application and to transfer the ultrasonic energy to the point of application. The converter
cannot be designed for each individual application due to cost considerations. Hence,
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sonotrode are essential for each application. Also, the amplitude of vibrations for some
application like machining and welding is not sufficient as generated by the converter. In
such cases, the amplitude of the vibrations has to be amplified by designed the sonotrode
with specific gain.
The transducer is mounted on the larger end of the sonotrode and the tool is mounted on the
smaller end. It works on the principle which states that velocity of sound wave is directly
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proportional to decrease in cross-sectional area. Thus to amplify the wave entry area is made
larger and the exit area is made smaller. Various taper functions can be implemented to
obtain this. The most common taper function is,
Double cylindrical(step cylindrical)

Conical (linear taper),

Exponential (exponential taper),

Catenoidal (hyperbolic taper),
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
Other special taper functions include mathematical functions like Gaussian tap Fourier
taper, but they are rarely used due to difficulties in manufacturing and amplification ratio of
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this special profile not being more than the basic profiles.
So, the most commonly employed shapes are step cylindrical, conical, exponential a
catenoidal due to the ease of manufacturing of step cylindrical and conical shape as
availability of standard function for exponential and catenoidal shapes in CNC controlled.
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Other profiles are generally combinations of these four profiles. [5]
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1.3 Concept of ultrasonic plastic welding
Ultrasonic plastic welding is the joining or reforming of thermoplastics through the use of
heat generated from high-frequency mechanical motion. It is accomplished by converting
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high-frequency electrical energy into high-frequency mechanical motion. That mechanical
motion, along with applied force, creates frictional heat at the plastic components' mating
surfaces (joint area) so the plastic material will melt and form a molecular bond between the
parts. Plastics assembly is a fast, clean, efficient, and repeatable process that consumes very
little energy. No solvents, adhesives, mechanical fasteners, or other consumables are
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required, and finished assemblies are strong and clean.
Ultrasonic Welding is the fastest and most cost effective method used today to join and
assemble plastic parts and non-ferrous metals. Ultrasonic welding is cost effective and a
green technology. Ultrasonic welding eliminates the need to use fasteners, glues and/or
solvents.
Ultrasonic Welding can be used to join all rigid thermoplastics, synthetic fabrics and films.
Ultrasonic welding uses an acoustic tool called an ultrasonic horn made to match your parts
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design. Ultrasonic Welding is converted to heat through friction that melts the plastic or
metal. The main components of an ultrasonic welding system are the actuator and power
supply, converter/booster & ultrasonic horn called the stack, part holding weld fixture/jig.
Material selection, Surface contact, Field of weld, Joint design, and Welding amplitude are
all factors in determining the proper booster and horn design for any given application.
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Understanding the following principles and your application requirements will much light
on this technology. [7]
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u.i
1.4 Process principal
Figure: 1.4 Ultrasonic plastic welding principal [7]
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A solid state welding process in which coalescence is produced at the faying surfaces by the
application of high frequency vibratory energy while the work pieces are held together
under moderately low static pressure. Ultrasonic welding, one of the most widely used
c.i
n
welding methods for joining thermoplastics, uses ultrasonic energy at high frequencies (20 –
40 kHz) to produce low amplitude (1 – 25 μ m) mechanical vibrations.
Electrical Energy is transformed into high frequency mechanical vibration. This mechanical
vibration is transferred to a welding tip through an acoustically tuned horn as shown in Fig
(1.3). The parts are scrubbed together under pressure at 20,000 cycles per second. This high
frequency vibration, applied under force, disperses surface films and oxides, creating a
et.
a
clean, controlled, diffusion weld. As the atoms are combined between the parts to be
welded, a true, metallurgical bond is produced. A process flow diagram can be found at the
end of this section illustrating the ultrasonic metal welding process. [7]
1.5 Principles of Ultrasonic Metal Welding (USMW)
Since most studies predominantly focus on ultrasonic plastic welding and its applications,
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the principles of USMW and its range of applications remain not fully understood. To
understand USMW, it is preferable to start with the principle of the technique, including any
variations or differences from other processes used in conventional welding systems. The
principle of the welding operation occurs from creating an oscillating shear force at the
interface between the mating surfaces, to disperse oxides, voids, liquids and contaminants,
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and offer new contact at many points. During the supply of vibration at a local area, the
resultant oscillation causes an increase in diffusion across the interface, resulting in a weld
similar to that produced by diffusion welding. At the bonding area, dynamic shear stresses
are generated due to the combined influence of static load and ultrasonic vibration. The
u.i
effects of interfacial slip and plastic deformation will increase the temperature of the
scrubbing area, which itself is always lower than the melting point of base metal. The
properties of the joining metals can influence the temperature at the interface between the
two surfaces, which means that the temperature can be higher for those metals with a low
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thermal conductivity such as steel, than for other types of metals which have high thermal
conductivity such as aluminium and copper. For that reason, the ultrasonic technique
consumes less power when it is applied to the welding of higher thermal conductivity metal,
compared to other processes such as resistance welding. [4]
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1.6 Ultrasonic Metal Welding (USMW)
Ultrasonic metal welding (USMW) was invented over 60 years ago and has since been used
to weld several types of metals and their alloys. USMW involves a solid-state joining
c.i
n
process in which metals are fastened together through the application of pressure combined
with localized high frequency shear vibrations at the welding zone. The action of high
frequency relative motion between the metals locally softens the overlap zone of the
specimens to be welded, forming a solid-state weld because of the progressive shearing and
deformation between surface asperities which disperses oxides and contaminants through a
et.
a
high frequency, scrubbing motion. This increases the area of pure metal contact between the
adjacent surfaces, in which the metal atoms are forced together to create a strong weld, as
shown in Figure 1.5. Welding is defined as a localized coalescence of metals or non-metals
produced by either heating of the materials to a suitable temperature with or without the
application of pressure, or by the application of pressure alone, with or without the use of
filler metal. Studies state that the ultrasonic welding of metals consists of complex processes
such as plastic deformation, work hardening, breaking of contaminant films, crack
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formation and propagation, fracture, generation of heating by friction and plastic
deformation, re-crystallization and inter-diffusion. In addition, slip and plastic deformation
are the two different mechanisms which control the nature of the solid-state bond in
u.i
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ultrasonic welding.
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Figure: 1.5 Schematic of the ultrasonic bonding region [4]
Recently, USMW has become a very popular technology for overcoming many of the
joining difficulties in the welding of similar and dissimilar metals, including plates, sheets,
foils, wires and ribbons, as well as many types of assembly which can be supported on an
anvil. Moreover, the process can be applied successfully for joining various metal work
pieces or bonding a metalized substrate, ceramic or glass using metal. Also, the process is
suited to the application of welding thicker gauges, due to its capacity for higher power
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systems. In addition, the USMW process is considered to be more efficient than other
conventional processes such as resistance welding in consuming a minimal amount of
energy .The USMW process is more reliable and applicable in certain cases with respect to
c.i
n
the other modern processes such as friction stir welding (FSW), because the energy
generated from the process is concentrated at the weld line compared to the top surface in
FSW. Although USMW and FSW are similar with the advantages of solid-state friction
welding, the welding cycle in USMW is very short compared to FSW, and the join produced
has good mechanical properties with less damage around the welding area. Generally, the
application of USMW depends on which way the two specimens are joined, using a
et.
a
combination of normal and shear forces. Friction also has an important role in creating a
scrubbing effect between the mating surfaces during the supply of vibration, whilst the static
force is applied normally to enhance the welding effect. While the USMW technique is
applied extensively to join metals, the widest current uses are typically for various alloys of
copper, aluminium, gold, silver, magnesium and related softer metal alloys. Therefore, it is
likely that the technique has a promising future for improving the joining of lightweight
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components in applications as diverse as electronics, automotive, medical devices,
aerospace and also increasingly in the sustainable energy industry in the manufacture of
products such as solar absorbers. The set-up of an USMW system is illustrated in Figure
1.6. From the figure it can be seen that the system components consist of ultrasonic
generator, transducer, booster and a horn, in addition to other welding components such as a
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rigid anvil, fixing tools and fixtures.
Figure: 1.6 Schematic of USMW system [4]
For most commercial welding systems, the maximum efficiency can be obtained in the
resonant condition of the system. Commonly, the line voltage of the electrical power is
converted into high frequency power, which can then be used for a wide range of metal
welding applications using a frequency between 15-70 kHz, or above 100 kHz in the case of
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micro-bonding. 20 kHz is usually the most popular frequency in USMW. The electrical
energy is supplied by a generator. The transducer converts electrical energy into mechanical
energy at the same frequency, through the use of a number of piezoceramic disks, but with a
c.i
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low amplitude resulting at the transducer working surface, typically in the range between
10-30 mm. Most welding systems will then adopt the use of a booster which controls the
vibration amplitude, and can serve as a mounting for the entire stack. However, this can lead
to an increase in the heating between connecting parts as well as resulting in a high stress at
the joining points. The horn is considered as a tool in the welding system which has the
ability to transmit ultrasonic energy from the transducer to the welding specimens and also
et.
a
to clamp the upper part of the substrate during the welding process. The low amplitude
generated from the transducer is then amplified by the booster and the horn and the
amplitude varies depending on the design of welding tools and the capacity of the generator.
The welding frequency is specified according to the application. At specific frequency,
higher amplitude at the horn working surface can result in higher power dissipation. In
ultrasonic welding, the machine is usually set by a certain mode. For example welding by
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time (an open-loop process) operates on the assumption that the fixed time results in a fixed
amount of energy delivered to the joint and that the sonic wave remains independent of the
energy. Welding by energy (a closed-loop process) is the second mode of operation. The
generator will measure the amount of power drawn and integrate it over time using feedback
control. When appropriate, the delivery of the ultrasonic energy is stopped by the generator
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whilst the energy is dissipated. The third welding mode involves welding by distance or
post-height, and allows joining by a specific weld depth. The ultrasonic generator will
continue delivering energy to the parts being welded until the preset displacement between
u.i
welding tool and surface metal is reached. [4]
1.7 Important parameters of the welding process
1) The duration of the welding operation, the welding time, ranges from 10ms up to
several seconds.
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2) The clamping pressure in the weld area.
This pressure equals approximately 0.1 to 0.3 times the Vickers hardness of the material to
be welded. The requirement values of the welding parameters (vibration, amplitude,
welding time, pressure) depend upon:
1) The thickness of the work piece contacting the welding tip, i.e. the upper work piece.
2) The material properties of the materials to be welded. [3]
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1.8 Special characteristics of ultrasonic metal welding
INTRODUCTION
1) Metals with widely different melting point can be welded (e.g. Al to Cu).
2) Thin foils or wire can be welded too much thicker part.
4) No fluxes or protective gas are needed. [3]
1.9 Plastic Welding Vs Metal Welding
c.i
n
3) Temperature in the weld area is below the melting point of the welded material.
1) The main difference is that in metal welding, the ultrasonic vibration is moving
parallel to the plane surface of the specimens being welded. In plastic welding, the
et.
a
vibrations are perpendicular to the surfaces.
2) Another reason is that the nature of the bond in metal welding is represented by a
solid-state, which means that no melt or fusion is required between adjacent
specimens, whereas in plastic welding, the process directly depends on the melting
of adjacent specimens. [4]
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1.10 Advantages of ultrasonic welding processes
Ultrasonic plastic welding exhibits unique welding properties that include:

Excellent electrical, mechanical, and thermal connections between similar and
dissimilar metals
Low heat build-up during the ultrasonic process (no annealing of materials).

Compensation for normal surface variations of the material.

Ability to clean surface oxides and contaminants prior to welding.

Ability to weld large areas using minimal energy.

Ability to weld thin materials to thick materials.

Low cost per weld

A sufficient energy input into the joining area has to be possible. Small joining areas
u.i
nfl

(<1 mm ²) must be realizable.
The reproducibility and the positioning accuracy have to be very high.

Flash should be as small as possible in order to ensure the functionality of the micro
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
system.

The mechanical load of the joining parts during. The welding process must be as low
as possible.

The energy input should be adjustable by variation of the welding parameters. [7]
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
Limited in joint thickness.

Challenging on high hardness materials.

May create audible noise from part resonance.

Part size is limited.

Process is unfamiliar to many engineers. [7]
1.12 Application of ultrasonic
et.
a
1.12.1 Cleaning
c.i
n
1.11 Disadvantages of ultrasonic processes
Perhaps the most common type of applications for ultrasonic is cleaning. This includes the
removal of grease, dirt, rust and paint from metal, ceramic, glass and crystal surfaces of
parts used in electronic, automotive, air craft, and precision instruments industry. Example
of specific applications is optical glass or lenses, quartz crystals, small ball bearings and
dental bridges. Ultrasonic testing of forging, casting and other metal parts has become
1.12.2 Machining
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standard. Examples of application are axles for vehicles and machine parts. [23]
Other industrial application for ultrasonic technology is the machining of materials.
Ultrasonic machining has the advantage over conventional, mechanical machining
techniques that it is well suited for processing unusual or complex shapes because no rotary
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toll required.
This technique can be used for very hard and highly abrasive materials because the actual
cutting is done by an abrasive material in a liquid carrier rather than a bit or blade which is
subject to abrasion. Among the materials that can be so processed are soft steel, ceramics,
u.i
glass and tungsten carbide. [23]
1.12.3 Soldering and welding
Ultrasound has also proved to be very useful for joining materials. It can be used for both
soldering and welding. In the case of soldering, the cavitations produced by high intensity
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ultrasonic waves destroys the oxide layer or aluminium, thus permitting parts to be joined
with tin soldering materials without the use of flux.
In ultrasonic welding pressure and heat generated by the intense vibratory action of material
to be welded and an ultrasonic welding head allows thin sheet of metal to be joined to a
much thicker section. Ultrasonic techniques can likewise be used to weld pieces of similar
or dissimilar plastic to each other. [23]
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1.12.4 Electronics
Ultrasonic technology is used extensively for the testing, cleaning and soldering of
1.13 Application of ultrasonic plastic welding
c.i
n
electronics components. [23]
Plastic welding is used for a huge variety of products ranging from blister packs, cartons
and small consumer goods up to car fuel tanks and dashboards.
Sewing machine control part.

To make the submersible pump impeller.

To weld the pneumatic control element.

It is mostly use in the medical and aerospace industries.

To join the automobile lightning part. [7]
1.14 Theoretical background
1.14.1 Physics of ultrasonic
et.
a

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Propagation of ultrasonic waves in an elastic medium is characterized by a displacement of
successive elements of the medium; a return to original position under the influence of
restoring forces; an over run of this original position due to inertia forces; and an oscillation
of diminishing amplitude about the starting point. Thus Passage of the waves through the
elements of material results in each element having a different displacement orbit. These
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phase differences are reflected in the different types of ultrasonic waves, a plot of the
displacements gives the graphical representation of the wave. The restoring forces oppose
the shear and tensile deformations. In the case of liquids and gases, tangential stress is not
opposed and elastic shear is not exhibited, thus the longitudinal vibrations or compression
u.i
waves, propagated in the direction of vibrating motion, are the only wave type that needs to
be considered. In the case of elastic solids, normal and tangential stresses occur.
Deformation due to shear stresses is propagated as transverse waves orthogonal to the
direction of vibration. [27]
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1.14.2 Ultrasonic wave’s types
The differing orbits of an element motion referred to above serve to define the wave types,
for example, if the orbit is sensibly parallel to the propagation direction the wave is
longitudinal; if orthogonal to the propagation path the wave is transverse or shear. [27]
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1.14.3 Longitudinal waves
This type is of particular interest for ultrasonic since they may be transmitted through solid,
liquid and gaseous media and generation and detection are relatively straightforward. The
c.i
n
velocity of propagation of sound waves is proportional and wavelength and the frequency:
cf
f 
1
t
Longitudinal waves have a high transmission velocity in most media and λ is small relative
to the cross-sectional area of the wave generator, (the transducer), which permits the
et.
a
focusing of sharp beam of energy. Since such waves effect a volumetric change in the
material of propagation they are classified as dilatational (as opposed to waves of distortion
which do not)
(  2G )(
 2v
 2v
)


(
)
X 2
t 2
This equation clearly implies uniqueness of particle velocity direction, the X direction; in
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fact, inertia effects of the path boundaries create some shear stress.
Longitudinal elastic vibrations in solid have considerable significance for ultrasonic
welding. Their propagation in a rod may be considered as successive zones of compression
and rarefaction. When a sound wave thus propagated is normally incident on a medium
having different acoustic impedance, it is reflected along the incident path. If the rod is of a
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length corresponding to exact multiple 0f λ/2 the resulting superposition of the incident and
reflected waves produces standing waves. These results into zones of compression
corresponding to min amplitude and zones of rarefaction related to peak amplitudes known
as nodes and antinodes of vibration respectively. In a standing wave intervals of λ/2 separate
u.i
the nodes the antinodes being situated at mid-interval position. [27]
1.14.4 Shear wave
The velocity of shear waves is approximately half that of the longitudinal waves thus λ for
shear waves is relatively short. This shortness of the wavelength means that shear waves
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will be subjected to dispersion or scatter within a material due to increased sensitivity to
inclusion. For a non homogeneous material, rotation of the transducer (the sending
component) may induce polarization, i.e. a different set of test readings may result, for
different angular orientation of the transducer. One merit of the lower velocities, however,
lies in the facility with which the electronics timing circuits may be adjusted since they will,
as a result, be less critical.
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Shear waves do not effect a volumetric change and are therefore classified as waves of
G(
 2v
 2v
)


(
)
y 2
t 2
c.i
n
distortion. The wave equation is:
The particle motion of shear wave is orthogonal to the direction of transmission and in the
case of y-cut crystal parallel to the x-axis. The effect of rotating the transducer is thus to
change the particle motion while maintaining the same transmission path. Considering, now,
the receiver, it will be seen that the strength of signal will vary from a maximum for
equivalent rotation to zero when crossed.
et.
a
Polarized wave velocity may vary according to the specific relationship of grain orientation
(and other physical characteristics) to the x-axis or to the degree of polarization of the shear
wave. This factor is significant, for example, in application demanding a pure shear
reflection. [27]
1.14.5 Surface waves
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These are often referred to as Rayleigh waves after Lord Rayleigh who, in 1885, used two
criteria for their definition:

That the dilatational wave and distortional waves are in combination and present
in the surface zones of the material in question;

That this combination is present only in surface zones.
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It may be shown that the velocity of Rayleigh waves is a function of motion along an axis
orthogonal to the pressure, since this displacement is a function of the elastic constant λ and
G, which govern the velocities of both distortional and dilatational waves. Surface wave
velocity is roughly 0.9 of shear wave velocity and λ is very short. [27]
u.i
1.14.6 Wave Generation
Fundamentally, longitudinal waves may be generated within a medium by the vibration of
any one of its surfaces in, a normal direction, at an ultrasonic frequency. For the energy to
remain in a beam the frequency f and the wavelength λ must be correctly related to the
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surface area vibrating.
Shear waves cannot be propagated through liquids or gases because there is virtually no
elasticity. They may be generated by the application of a shearing force to the face of a
material, i.e. imparting a rocking motion parallel to the surface. Surface waves are generated
by a similar mode to shear waves, the areas of vibration being specifically rectangular. [27]
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1.14.7 Propagation of Elastic Waves in Solids
Both longitudinal and shear / transverse waves exits in solid; in case of longitudinal waves
alternating pressure is replaced by alternating stress (Figure 1.7 a). Solids can also carry
c.i
n
other types of waves; an infinite medium can transmit shear / transverse waves (Figure 1.7
b). The velocity of shear waves is always below that of longitudinal waves and this is
controlled by shear modulus, whereas that of longitudinal waves is governed by the bulk
modulus. Both types of waves can occur independently.
A finite body in addition can support waves involving bending; there are also others such as
compression waves in rods. Waves in rods whose transverse dimensions are small are
et.
a
influenced by the Poisson effect (transverse expansion in response to longitudinal
compression) which is characterized by the ratio of these, which is denoted by µ and varies
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u.i
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from 0.2 to 0.35.
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Figure: 1.7 (a) Longitudinal Wave [27]
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INTRODUCTION
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et.
a
c.i
n
CHAPTER-1
Figure: 1.7 (b) Shear Wave [27]
The transverse effect arising from this effect in longitudinal wave are not apparent for an
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infinite body (infinite wave front); because the effects in adjacent parts are in opposition
(the individual areas experience hydraulic compression). A thin rod allows this lateral
expansion, so travelling swelling occurs. This makes the material effectively of lower
rigidity; the deformation is governed by Young’s modulus, which is always lower than the
u.i
bulk modulus. Propagation in an unbounded solid and in a thin rod represent extreme cases;
a rod of diameter neither large nor small relative to the wavelength shows complicated
effects and the velocity of propagation lies between c∞ and c.
Bending and tensional waves can occur in rods and longitudinal radial waves also (if the
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radius is larger than the wavelength). Surface wave can propagate on any free surface.
These waves can occur singly or in combination, so the wave pattern can be complicated.
Any change in the propagation condition, such as reflection at an interface, may cause one
wave type to change another. [27]
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LITERATURE REVIEW
(1) Analysis of Different Shaped Sonotrode used for Plastic Welding
A. Dipal M. Patel, B. Avadhoot U. Rajurkar, Published in institute of technology, Nirma
University, Ahmadabad – 2011
c.i
n
They described procedure of sonotrode design for conventional shape profile by classical
method and by CARD software and presented comparison of results. They carried out
analysis for step-cylindrical, conical and exponential shape profiles of sonotrode. [8]
(2) Computational modeling and experimental studies of the dynamic performance of
ultrasonic horn profiles used in plastic welding
et.
a
M. Roopa Rani, R. Rudramoorthy, published in Science Direct (2013)
They described the design of different type of horn profile like Cylindrical, Gaussian,
Catenoidal, Stepped, and Bezier. They have done the harmonic analysis. Temperature
developed during the welding of ABS test parts using different horns is recorded using
sensors and National Instruments (NIs) data acquisition system. The recorded values are
compared with the predicted values.
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They conclude that welding using a Bezier horn has a high interface temperature and the
welded joints had higher strength as compared to the other horn profiles. The used Alloy
AA 6351 material for horn fabrication. [9]
(3) Study on ultrasonic stepped horn geometry Design and FEM simulation
Eng. Alexandra sergiu nanu, prof. niculae ion marinescu, published in Nonconventional
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Technologies Review – no. 4/2011
The paper deals with study through Finite Element Method (FEM) of ultrasonic stepped
horn used to aid electro-discharge machining (EDM+US). Several studies were carried on
in order to analyze the influence of steps lengths and diameters and corner radius size on
u.i
own frequency of stepped ultrasonic horns. A good agreement between the FEM results and
theoretical and experimental data was emphasized. They also developed design procedure of
stepped horn. [10]
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(4) The design of acoustic horns for ultrasonic insertion
Kuen-Ming Shu, Hsieh, Wen- Hsiang, Chien Chih Chen, published in Technology National
Formosa University-2002
They classified horn on resonant length. Sonotrodes are classified as half wave length
sonotrode (λ/2 Length), Full wave length sonotrodes and so on. Sometimes half wavelength
sonotrodes are made by combining two quarter wave length sonotrodes of different shape
profile (λ/4+λ/4 Length).Combination of cylindrical shape + exponential shape, cylindrical
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LITERATURE REVIEW
shape+ conical shape, exponential shape + cylindrical shape and conical shape + cylindrical
shape are example of λ/4+λ/4 length sonotrodes. They carried out calculation for combine
shape profile of horn for cylindrical + conical as well as conical + cylindrical shape (λ/4+λ/4
c.i
n
Length) by mathematical equations and by ANSYS. They measured performance of
commercial available horn and carried out comparison of theoretical dimension of conical
horn with commercial available horn. [11]
(5) Ultrasonic horn design for ultrasonic machining technologies
M. Nad’ published in Applied and Computational Mechanics 4 (2010) 79–88
They carried out theoretical numerical analysis of various horn profiles the natural
et.
a
frequency and amplification factor of sonotrode in resonant state was study for different
geometrical shapes and dimensions. Detailed graphical presentation of result of the effect of
horn shape parameters were presented in such a way that it can be useful for selecting
suitable sonotrode shape with require properties. [12]
(6) The Effect of the shape parameters on modal properties of ultrasonic horn design
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for ultrasonic assisted machining.
Nad, M.; Cicmancova, L. published in 8th International daaam Baltic Conference industrial
engineering 2012
They performed analysis of effect of on horn geometry shape (cylindrical, taper, and
exponential) by use of wave theory and FEM analysis. Graphical representation of results of
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the effect of horn shape parameters such as slenderness ratio, taper angle, exponential
constant were prepared. [13]
(7)Design of an Ultrasonic steel horn with a Bezier profile
Hai-Dang Tam Nguyen, Dung-An Wang, Published in International Conference on Green
u.i
Technology and Sustainable Development September 29-30, 2012.
A novel ultrasonic steel horn with a Bezier profile is developed. The first longitudinal
displacement mode of the horn is exploited for high displacement amplification. An
optimization scheme and finite element analyses are used to design the horn. The
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displacement amplification and stress distribution characteristics of the Bezier horn and
catenoidal horn are examined. Experimental results of the harmonic response of the
fabricated horn confirm the effectiveness of the design method. The displacement
amplification of the proposed horn is 62% higher than that of the traditional catenoidal horn
with the same length and end surface widths. [14]
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(8) The parametric design of the ultrasonic exponential horns
LITERATURE REVIEW
Iulian stǎnǎşel, Flavius Ardelean, published in Nonconventional Technologies Review – no.
4/2010
c.i
n
Presented computer aided design procedure of exponential shape profile using classical
relationship. They used MATLAB as a CAD tool. They integrated the output design data of
MATLAB program for parametric solid modelling. It was claimed that this solid model can
be used for further analysis and preparation of CNC program for manufacturing [24]
(9) Parametric Effect of Ultrasonic Plastic Welding On Tensile Strength for ABS,
et.
a
Acrylic and Polycarbonate Materials.
Sunilkumar K. Patel, Prof. Dhaval M. Patel, published in International Journal of
Engineering Research & Technology (IJERT) March – 2013
They describe tensile strength of
polycarbonate, acrylic and ABS material welded by
ultrasonic welding with different parameter. They use taguchi method for experiment
analysis.They conclude that the weld time is most significant control factor on Tensile
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strength during ultrasonic plastic welding. They did ANOVA analysis also.
(10) Ultrasonic welding of advanced Thermoplastic composites: an investigation on
energy directing surfaces
I. Fernandez, D.Stavrov, H.E.N. Bersee, published In Delft University of Technology
Kluyverweg 1, 2629 HS Delft
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They describe different energy directing surfaces for ultrasonic welding of advanced
thermoplastic composites. They used continuous carbon fiber reinforced polyetherimide
(CF/PEI). They used three types of energy directors; the basic transverse energy director,
T1, was compared with the single parallel, P1, and with the double parallel, 2P½. They
u.i
conclude that (1) the coverage of the overlap area can be enhanced when using multiple
energy directors, provided that their location and size do not hinder the flow of resin.
(2) Multiple energy directors significantly reduce the disturbance of the fibers in the
outermost layers of the welded parts.
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(3) Transverse energy directors provide less scatter in the amount of welded area than
parallel energy director configurations.
(4) An excessive amount of resin at the welding interface leads to decreased strength of the
weld. There is, however, a wide range of resin volumes for which welds with a satisfactory
strength level can be obtained. [25]
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(11) Ultrasonic welding of micro plastic parts
W. Michaelia, E. Haberstrohb, W.-M. Hoffmanna, published in Institute of Plastics
Processing (IKV), RWTH Aachen University, Aachen, Germany
c.i
n
They study about tensile strength of micro parts of amorphous polymer polycarbonate (PC)
and polyoxymethylene (POM) and conclude that At an amplitude of â = 16.5 μm, a joining
displacement of sw = 0.1 mm and a welding velocity of vw = 0.6 mm/s the best result could
be achieved for PC. Normally, POM features a good weldabilty with ultrasonic welding.
However, it was not possible to prevent the partial decomposition recognized at high
amplitude with PC when welding the depicted sample part geometry with the three-
et.
a
dimensional weld seam geometry. [26]
(12) Experimental studies on joining copper wire - copper sheet using ultrasonic metal
welding
J.PRADEEP KUMAR & 2K.PRAKASAN published in International Journal of
Mechanical and Production Engineering Research and Development (IJMPERD) 2012.
ibn
In this paper they study of ultrasonic welding of copper wire (1.2mm diameter) to thin
copper sheet (0.2 mm) as many of the industrial applications are in need of this kind of
contact technology. Quality of the welded joints is evaluated based on mechanical tests and
the quality criterion is then applied to evaluate the weldabilty. They also developed second
order regression model equation to predict the weld strength of the joint based on the
nfl
experiments conducted using full factorial design of experiments. In this they select the
Weld pressure (bar), Amplitude (μm), Weld time (sec) as control variable.
They conclude that the weld pressure accounts to 50 % influence on the response-weld
strength. This is to be expected since as the pressure increases, sonotrode holds the work
u.i
pieces without significant amount of rubbing. The other parameters like amplitude and the
interactive effect of weld pressure and weld time influences the weld strength significantly
by 16% and 17% respectively. [15]
(13) Direct welding of different metals used ultrasonic vibration
gn
Shin-ichi Matsuoka, Hisashi Imai, Published in journal of materials processing technology
2009
This paper describes an experimental study on ultrasonic welding of aluminium and copper
alloy. The ultrasonic welding of Al/Cu can be accomplished when the conditions of
amplitude: 15µm, welding pressure: 20MPa, at a required duration of 1.0 s under the water
bath. Furthermore, the oxide film and organic coating are periodically removed from
M.TECH (AMT)
Page 22
CHAPTER-2
LITERATURE REVIEW
bonded interfaces by ultrasonic wave vibration, and it can be expected to form transition
layer of 1–2µm at the bonded interface
They conclude that:
c.i
n
(1) Tests of welding of Al alloys with different properties show that satisfactory welding is
possible in any test and, in particular, That the magnitudes of the welding pressure and plate
thickness largely affect the welding properties. The welding pressure Pc and vibration
energy E largely concern the welded strength, and the following relation was introduced:
E=
.
(2) Underwater welding requires a somewhat larger welding pressure and longer welding
et.
a
time compared with atmospheric welding, however, the obtained strengths of the welded
materials are equal and can suppress heat at the heat-affected part in the vicinity of the
welding interface.
(3) SEM observation of the welding interface shows that oxide films and organic films on
the material surface can be removed along the frequency of vibration, allowing welding of
newly formed faces. A satisfactory welding interface can be obtained causing neither hollow
ibn
pores nor exfoliation. [16]
(14) Process robustness of single lap ultrasonic welding of thin, dissimilar materials.
T.H. Kim a, J. Yuma, S.J. Hu, J.P.Spicer b, J.A. Abell, published in CIRP Annals Manufacturing Technology 60 (2011)
This paper presents a process robustness study of ultrasonic welding of thin metal sheets.
nfl
Quality of the welded joints is evaluated based on mechanical tests and the quality criterion
is then applied to evaluate the weldabilty. These results were used to determine both the
optimal weld parameters and the robust operating range. In this they use 0.2mm thick
copper sheet & 0.2mm thick nickel plate. They done T-peel test for weld quality, pressure
u.i
and welding time are selected by them as control variable. They conclude the output
response decreased in the region where there was a long welding time and high welding
pressure because of crack around the weld caused by the excessive mechanical vibration.
While the output decreased at the region at a short welding time and a low welding pressure
gn
because of insufficient energy. [17]
M.TECH (AMT)
Page 23
CHAPTER-2
LITERATURE REVIEW
(15)Experimental investigations on optimization of ultrasonic welding parameters for
copper to brass joints using response surface method and genetic algorithm
Advanced Engineering Research and Studies-2012
International Journal of
c.i
n
S Elangovan , S Venkateshwaran , K Prakasan published in
In this paper an effective methodology is developed to determine the optimum welding
conditions that maximize the strength of joints produced by ultrasonic welding by coupling
response surface method (RSM) with genetic algorithm (GA).
They concluded that weld strength increases with increases of amplitude because increase in
amplitude gives increased area for rubbing action between the metallic surfaces that leads
et.
a
better bonding and increase of weld strength. Also, weld strength increases with increase of
pressure because increase in pressure causes asperities of the two surfaces come in to close
contact which allows van-der Waals forces to take effect which leads to better bonding and
increase of weld strength. In some cases weld strength increases up to 3.0 sec. Beyond 3.0
sec weld time, the weld strength start decreasing for any value of pressure and amplitude
because excessive weld time affects the existing molecular bond in the joint.
ibn
In some cases weld strength increases considerably up to 3.5 bar. Beyond 3.5 bar, the weld
strength again start decreasing for any value of amplitude. This is because increase in
clamping force (pressure) reduces the relative motion between surfaces leading to reduced
area of contact and hence reduced strength. [18]
nfl
(16) Optimization of ultrasonic welding parameters and temperature distribution in metal
matrix composite based on aluminum
Marius POP-CALIMANUa, Dinu GUBENCUa, Ioana POP-CALIMANU, Traian
FLESER, published in University of Timisoara, Faculty of Mechanics -2013
In this paper were optimized the parameters of ultrasonic welding like the welding pressure,
u.i
welding time and amplitude of vibrations to obtain a good bonding of AA2124/SiC/25%pT4 metal matrix composite using a 2 full factorial design. Of course, we are interested to
know which variable of the process affect most the response. The experiment is performed
gn
using AA2124/SiC/25%p-T4 metal matrix composite under thin foil form with 1 mm
thickness.
They conclude that (1) welding time (A), welding pressure (B) and the interactions between
those two, are the influence factors that have the greatest effect on the temperature, but not
on the quality of the bond. To refer to the bond quality we must take into account the
vibration amplitude of sonotrode, because it has a very important role in ultrasonic welding
process.
M.TECH (AMT)
Page 24
CHAPTER-2
LITERATURE REVIEW
(2) Where increasing the one or the both major influence factors, will increase the
temperature generate during the ultrasonic welding process, and the big problem is when we
grow also in the same time the vibration amplitude factor that has harmful effect on bond
c.i
n
quality.
(3) Highest temperature recorded is at the end of the welding cycle. It can be seen that
during the ultrasonic welding process, the temperature increase very rapidly at the beginning
of the weld, and if we increase the welding time and welding pressure, also will increase the
temperature. [19]
(17) Ultrasonic welding between mild steel sheet and Al–Mg alloy sheet.
et.
a
TakehikoWatanabe, Hideo Sakuyama, Atsushi Yanagisawa, published in Journal of
Materials Processing Technology 209 (2009) 5475–5480
Ultrasonic welding between SS400 mild steel sheet and aluminum alloy sheet containing
magnesium (A5052) was conducted. In this study, authors investigated the influence of
ultrasonic welding conditions on the mechanical properties and the interface microstructure
of a joint, and the effect of insert metal was examined to improve the joint strength. The
ibn
strength of the joints welded using various clamping forces and constant welding time of 1.0
s showed the maximum value at the clamping force of 588N and decreased with the
clamping force over 588N because the excessively large clamping force reduced the
frictional action at the interface. The strength of the joints welded using the constant
clamping force of 588N and various welding times showed the maximum value at the
nfl
welding time of 2.5 s. However, the strength of the joint welded using the welding time of
3.0 s decreased due to the formation of Fe2Al5 intermetallic compound at the interface.
Using the insert metal of commercially pure aluminum, the joint strength was successfully
improved and the strength of the welded using 3.0 s welding time was about three times as
gn
u.i
large as that of the joint without the insert metal. [20]
M.TECH (AMT)
Page 25
CHAPTER-3
DESIGN & MANUFACTURING OF HORN (SONOTRODE)
3.1 Introduction
In this chapter includes design of horn and material selection for horn. Horn design is very
important for ultrasonic application. Even the simplest small diameter-round horn has been
c.i
n
dimensioned to resonant with very precisely.
3.2 Selection of material
Depends of application may dictate certain requirements, such as wear resistance. If so,
these will be in addition to the common requirements for sonotrode material: high fatigue
resistance and low acoustic losses (meaning that they shouldn’t absorb to much energy from
et.
a
vibration) high strength alloys of steel, aluminum and titanium are ideal, many other
material might be sued but at the risk of high power losses.
In this work EN24 (AISI 4340) alloy steel used for horn material, there properties are as
under.
Table 3.1 Properties of EN24 [28]
Unit
7850
Kg/m
Elastic modulus
210
Gpa
Sound velocity
5334
m/s
Yield strength
470
MPa
Bulk modulus
140
GPa
Shear modulus
80
GPa
Tensile strength
745
MPa
1427
°C
gn
u.i
nfl
Density
Value
ibn
Name
Melting point
M.TECH (AMT)
Page 26
CHAPTER-3
3.3 Theoretical Design of Sonotrode
Sonotrode works on principle which states when sound wave passes through a medium
sound velocity increases with decrease in cross-sectional area of the medium. Thus, from
c.i
n
above statement it obvious that sonotrode are having different areas at two ends i.e. exit area
is made smaller than the entry area. It is designed on the basis of elastic vibration of an
elastic member with varying cross-section. For design of sonotrode three parameters are
highly important;
1) Gain or Transformation Ratio,
2) Distribution of Amplitude and Stress,
et.
a
3) Location of Nodal and Anti-Nodal Points.
Let us consider the free-free vibration of a non-uniform bar, in general as shown in Figure
3.1,
Assuming,
1) Plane wave propagation in the rod along the axial direction and
u.i
nfl
ibn
2) Wave propagation along lateral directions is neglected.
Figure: 3.1 Schematic of a free vibration of a non-uniform bar
An elementary section taken at distance x from one end of thickness dx will be subjected to
gn
different stress level due to a stress gradient of
δσ
δ
which will produce a strain in the
elementary strip as,
Strain =
.

(3.1)
x is the stress level on the section x of area A.
Hence,
M.TECH (AMT)
Page 27
CHAPTER-3
 =
.
(3.2)
Due to vibration the elementary strip shall be acted upon by an accelerating force Fa as,
=
.
.
.
Neglecting (dx)2 term,

=
. .
.
(3.3)
c.i
n

.
(3.4)
The constraining force acting on the elementary strip,
Neglecting (dx)2 term,
F =
A.

. dx +  .
Equating eq. (3.4) and (3.6)

A.
+  .
. dx − 
. dx . A +
et.
a

F =  +
=
. dx

. .
(3.5)
(3.6)
(3.7)
A. E.
ibn
Substituting the value of (x) and (x/x) from eq. (3.2) in eq. (3.7),
+ E.
.
=

. .
(3.8)
Now, the displacement equation for angular frequency  can be written as,
nfl
From which,
v = G sin t + H cos t ,
= − v
(3.9)
(3.10)
Which again substituted in eq. (3.13) gives,
.
u.i
+
.
=

(3.11)
Eq. (3.11) is the generalized equation of wave propagation in sonotrode that may be of any
taper type.
gn
For known specified sonotrode shapes, the above partial differential equation is reduced to
ordinary differential equation (ODE). ODEs for exponential, conical and step-cylindrical
shaped sonotrode are calculated. Following topics deal with design of sonotrode for these
taper functions.
M.TECH (AMT)
Page 28
CHAPTER-3
3.3.1 Exponential Profile
Input data
d1=30mm
d2=6mm
c.i
n
c=5334m/s
w=2ᴨf, f=20 KHz
For exponential taper,
A = A1 e nx
(3.12)
n = 2
d= d e
Now to get equation of amplitude
= −n
Thus,
Amplitude:

+
= 0
ibn
− n.
et.
a
Thus,
(3.13)
(3.14)
(3.15)
(3.16)
General solution of the eq. (3.16) is,
v cos


–
nfl
v =
–

sin


e
(3.17)
(3.18)

Or
u.i
c =

c = c 1 +

(3.19)
gn
Eq. (3.18 and 3.19) gives optimal value of the c.
Thus, the effect of taper is to increase effective velocity of sound waves in the medium by
factor 1 1–

. From the eq. (3.18) it is obvious that the velocity is real only if n <
(2/c). Thus, it is a limiting value for the amount of taper.
M.TECH (AMT)
Page 29
Stress:
x =
Transformation ratio:
−
a = √

.
=

+


=
Resonance length:

 
(3.20)
(3.22)

et.
a
Nodal point:

(3.21)
Where, a= transformation ratio
=
sin
c.i
n
CHAPTER-3
= /2
(3.23)
Nodal point is a point where velocity of sound in the medium attains zero value. It is
available by equating velocity equation to zero.




/2) and (−
end, i.e. xn < /4.
Anti-nodal point:
=



(3.24)
( )/) are positive, anti-nodal point is towards the smaller
ibn
Since, (−
=
It is a point where stress in the medium is maximum.

= 0
nfl
At anti-nodal point
=




=



(3.25)
Since, (-nc/2) and (-ln (a)/) are negative, anti-nodal point is towards the smaller end i.e.
u.i
xa > /4. Thus both the points are equidistance from the midpoint but nodal point is before
mid point and anti-nodal point is after the midpoint.
3.3.2 Conical Profile
gn
Similarly for conical taper sonotrode, all the desired design parameters are calculated and
summarized as below. For conical taper cross sectional area A is given by,
Where,  = w/c
M.TECH (AMT)
=
=
1 1− 
1 1− 
(3.26)
(3.27)
Page 30
CHAPTER-3
Thus,

(3.28)

c.i
n
=
Hence generalized equation of wave propagation in sonotrode for conical profile is,
−
Amplitude:
α
.α
.

+
= 0
(3.29)


.
–

.


(3.30)
et.
a
=
At the same time following condition must be complied,

=
Stress:




−


–
Transformation ratio or gain
=


+

1−

− 

+
(3.31)
(3.32)
(3.33)

=
u.i



nfl
Resonance length:

ibn
 =

–

(3.34)
Nodal point:
gn
Anti-nodal point:
=

− 1


xa =x, where,  = max(x)
M.TECH (AMT)
(3.35)
(3.36)
Page 31
CHAPTER-3
3.3.3 Step-Cylindrical Profile
Similarly for step-cylindrical sonotrode, all the desired design parameters are
calculated and summarized as below.
A = constant
c.i
n
d = constant
Thus,
/
= 0
Hence generalized equation of wave propagation in sonotrode for step-cylindrical profile is,
= 0
(3.37)
et.
a
Amplitude:

+
= −

.
For, - l1<=x<=0
.
Stress:

.
For, 0<=x<=l2

sin

. cos
nfl
 = − Ev
For, - l1<=x<=0

= −

u.i


.
For, 0<=x<=l2


–
ibn
= −

.

–
+ cot


+
.

(3.38)

.
. sin

(3.39)

(3.40)
.

(3.41)
Transformation ratio:
gn

M.TECH (AMT)
=

(3.42)
Page 32
=  /
Nodal point:
=
=
(3.43)

cot

For, 0<=x<=l2

tan
cot


(3.45)
(3.46)
For, - l1<=x<=0

tan
cot

(3.47)
ibn
x =
(3.44)
For, - l1<=x<=0
Anti-nodal point:
x =

cot
c.i
n
Resonance length:
et.
a
CHAPTER-3
For, 0<=x<=l2
3.4 Design using CARD software
3.4.1 Overview of CARD
nfl
Computer Aided Resonator Design (CARD) is software that applies quantitative techniques
to the design of ultrasonic resonators (horns, boosters, and transducers) that vibrate in a
longitudinal mode. CARD provides assistance in the design of resonators having low-tomoderate complexity. With CARD, alternative resonator designs can be quickly evaluated
u.i
without machining and testing. The effects of proposed resonator modifications can be
easily determined. CARD is especially useful for designing low-stress resonators, resonators
with a specified gain, and resonators with a specified node location.
CARD automatically tunes the horn to the desired frequency by adjusting the resonator
gn
dimensions. The adjustable dimensions include the length, thickness or diameter, and
location of a transition radius. In addition, CARD can automatically adjust the gain and
minimize the stress. CARD calculates numerous acoustic parameters, including tuned
length, tuned frequency, gain, node location, maximum stress, stored energy, loss, overall
quality factor (Q), and weight. When calculating the stress, CARD considers the effect of
stress concentrations at radii and slot ends. CARD graphically displays the calculated
M.TECH (AMT)
Page 33
CHAPTER-3
amplitude, stress, and strain-loss distributions at each point along the length of the
resonator.
The resonator shape can be graphically displayed to verify its correctness. The resonator can
c.i
n
be composed of multiple, user-defined materials. The resonator can have a cavity in the face
and can have studs, wrench flats, and spanner wrench holes.
CARD allows up to 10 different user-defined materials and ultrasonic equipment
configurations. These defaults can be saved to disk. CARD is very easy to learn and use, so
that even those with minimum computer experience should have little difficulty. All user
input is from menus; there are no commands to memorize. From any menu within CARD, a
et.
a
single key press will change between metric and English units. Extensive hypertext help is
available for each menu option. Also included with the help is a glossary of over 300
acoustic terms. (Note: although CARD is very easy to use, the user must have some
understanding of resonator design in order to evaluate the computer-generated output.)
In addition to CARD's main analysis, CARD also has a section devoted to theoretical and
empirical. CARD also includes a database of metric and English bolt dimensions. Other
3.4.2. Limitations
ibn
sections include calculations for press-fits, bolt stresses, and piezoelectric ceramics.
Because CARD uses a one-dimensional analysis, there are limitations on the parameters that
can be calculated. Amplitude uniformity across the input and output surfaces cannot be
calculated since the amplitude is not permitted to vary across each slice. Similarly, the
nfl
frequencies of non axial resonances cannot be determined. However, this is not a severe
limitation, since the majority of resonators for which CARD is suitable do not have
problems with non axial resonances.
CARD designs resonators by looking at a side view of the resonator. (For slotted bar horns,
u.i
this is the side view where the slots cannot be seen.) When looking at the resonator from the
side, the resonator cross-section must be symmetric about the resonator axis (i.e., the crosssectional shape on one side of the resonator axis must be the same as the shape on the other
side of the resonator axis). Thus, CARD cannot analyze resonators with asymmetric face
gn
contours, resonators with asymmetric face bevels, etc. unless these can be reduced to an
equivalent symmetric design.
M.TECH (AMT)
Page 34
CHAPTER-3
Table 3.2 Typical input parameter of CARD
Parameter
Value
Unit
1
Material
EN24(AISI 4340)
2
Thin wire wave speed
5334
m/sec
3
Modulus of elasticity
210
GPa
4
Density
5
et.
a
c.i
n
Sr.
Kg/m3
Input frequency
20000
Hz
6
Big end diameter
30
mm
7
Small and diameter
6
mm
8
Input resonant length
160 (Conical)
mm
151.8 (Exponential)
mm
133.35 (Step-cylindrical)
mm
gn
u.i
nfl
ibn
7850
M.TECH (AMT)
Page 35
ibn
et.
a
c.i
n
CHAPTER-3
gn
u.i
nfl
Figure: 3.2 Stress diagram for conical shaped sonotrode profile
Figure: 3.3 CARD result for conical shaped sonotrode profile
M.TECH (AMT)
Page 36
et.
a
c.i
n
CHAPTER-3
gn
u.i
nfl
ibn
Figure: 3.4 Stress diagram for step-cylindrical shaped sonotrode profile
Figure: 3.5 CARD result for step-cylindrical shaped sonotrode profile
M.TECH (AMT)
Page 37
ibn
et.
a
c.i
n
CHAPTER-3
gn
u.i
nfl
Figure: 3.6 Stress diagram for Exponential shaped sonotrode profile
Figure: 3.7 CARD result for Exponential shaped sonotrode profile
M.TECH (AMT)
Page 38
CHAPTER-3
Table 3.3 Values of Different shaped Horn
Parameters
Input Parameters
30
D2
6
Material
EN24
30
6
et.
a
D1
Dimension by
theoretical
equation(mm)
c.i
n
Dimension by CARD
software(mm)
D1/D2
Frequency
EN24
5
5
20kHz
20kHZ
Output for the conical shaped horn
158.7
ibn
L
3.41
Transformation Ratio
160
4.79
Output for Exponential horn
nfl
L
149.6
151.8
4.85
5
Output for step-cylindrical horn
u.i
L
132.2
133.35
1.16
0.99
3.5 Manufacturing of horn
gn
The stepped cylindrical and conical shapes are the least complicated to machine. The
traditional approach to manufacture the horn is to use lathe. But shapes like exponential and
hyperbolic require NC/CNC machining. The horn should be free of sharp transitions and
tool marks, because they can cause stress risers that lead to cracking.
M.TECH (AMT)
Page 39
CHAPTER-3
Figure: 3.8 (a) conical horn
et.
a
c.i
n
By using lath, prepared conical and step-cylindrical horn from EN24 material.
(b) step-cylindrical horn
(c) Exponential horn
ibn
For the exponential shape CNC machine require and for that CNC program require. For the
CNC program first prepare the model in solid works software then using NX8 software
creates a CNC program. Using this program prepared exponential horn as shown in above
gn
u.i
nfl
figure.
Figure: 3.9 Model in solid works
M.TECH (AMT)
Page 40
CHAPTER-3
3.5.1 Program generated by NX8
N0260 X41.6
N0530 X-1.6 F.4
N0020 T0007 M06
N0270 Z1.95
N0540 X-3.2 F1.
N0025 S2000 M03
N0280 G01 X40. F.4
N0030 G95 G00 G90
X41.162 Z2.95
N0290 X-1.6 F.4
N0040 G01 X39.562 F.4
N0050 X-1.6 F.5
N0080 X41.483
N0090 Z2.7
N0130 G00 Z5.7
N0150 Z2.45
N0160 G01 X39.997 F.4
N0170 X-1.6 F.4
u.i
N0180 X-3.2 F1.
N0190 G00 Z5.45
N0200 X41.6
gn
N0210 Z2.2
N0220 G01 X40. F.4
N0230 X-1.6 F.4
N0240 X-3.2 F1.
N0250 G00 Z5.2
M.TECH (AMT)
N0570 Z.7
N0580 G01 X40. F.4
N0590 X-1.6 F.4
N0600 X-3.2 F1.
N0340 G01 X40. F.4
N0610 G00 Z3.7
N0350 X-1.6 F.4
N0620 X41.6
N0360 X-3.2 F1.
N0630 Z.45
N0370 G00 Z4.7
N0640 G01 X40. F.4
N0380 X41.6
N0650 X-1.6 F.4
N0390 Z1.45
N0660 X-3.2 F1.
N0400 G01 X40. F.4
N0670 G00 Z3.45
N0410 X-1.6 F.4
N0680 X41.6
nfl
N0140 X41.597
N0560 X41.6
N0330 Z1.7
ibn
N0100 G01 X39.883 F.4
N0550 G00 Z3.95
et.
a
N0070 G00 Z5.95
N0120 X-3.2 F1.
N0310 G00 Z4.95
N0320 X41.6
N0060 X-3.2 F1.
N0110 X-1.6 F.4
N0300 X-3.2 F1.
c.i
n
N0010 G71 G90 G95
N0420 X-3.2 F1.
N0690 Z.2
N0430 G00 Z4.45
N0700 G01 X40. F.4
N0440 X41.6
N0710 X-1.6 F.4
N0450 Z1.2
N0720 X-3.2 F1.
N0460 G01 X40. F.4
N0730 G00 Z3.2
N0470 X-1.6 F.4
N0740 X41.6
N0480 X-3.2 F1.
N0750 Z0.0
N0490 G00 Z4.2
N0760 G01 X40. F.4
N0500 X41.6
N0770 X-1.6 F.4
N0510 Z.95
N0780 X-3.2 F1.
N0520 G01 X40. F.4
N0790 G00 X67.07
Page 41
CHAPTER-3
N0800 Z17.196
N1080 Z-152.2 F1.
N0810 X33.5 Z3.581
N1090 G00 X33.5
N0820 G01 Z2.781 F.7
N1100 Z3.8
N0830 Z-151.181 F.5
N1110 X31.
N0840 Z-151.981 F1.
N1120 G01 Z3. F.7
N0850 G00 X35.5
N1130 Z-148.788 F.7
N0860 Z3.742
N1140 G02 X31.38 Z149.973 CR=691.139
N0880 G01 Z2.942 F.7
N0890 Z-151.342 F.7
N1330 G00 X32.
c.i
n
N1340 Z3.8
N1150 G01 X31.435 Z150.145 F.7
N1350 X29.5
N1360 G01 Z3. F.7
N1370 Z-143.973 F.7
N1380 G02 X30. Z145.603 CR=691.139
et.
a
N0870 X33.
N1320 G01 X31.631 Z146.642 F1.
N0900 Z-152.142 F1.
N1160 X31.
F.5
N0910 G00 X35.
N1170 Z-151.4 F.7
N1410 Z3.8
N0920 Z3.798
N1180 Z-152.2 F1.
N1420 X29.
ibn
Z-150.93
N1390 G01 X31.131 Z145.037 F1.
N1400 G00 X31.5
N1190 G00 X33.435
N1430 G01 Z3. F.7
N0940 G01 Z2.998 F.7
N1200 Z3.8
N1440 Z-142.316 F.7
N0950 Z-151.398 F.7
N1210 X30.5
N1450 G02 X29.5 Z143.973 CR=691.139
N0930 X32.5
N0960 Z-152.198 F1.
N1220 G01 Z3. F.7
N1230 Z-147.208 F.7
N1460 G01 X30.631 Z143.407 F1.
N0980 Z3.8
N1240 G02 X31. Z148.788 CR=691.139
N1470 G00 X31.
nfl
N0970 G00 X34.5
N0990 X32.
N1480 Z3.8
N1010 Z-151.4 F.7
N1260 G00 X32.5
N1500 G01 Z3. F.7
N1020 Z-152.2 F1.
N1270 Z3.8
N1510 Z-140.632 F.7
N1030 G00 X34.
N1280 X30.
N1040 Z3.8
N1290 G01 Z3. F.7
N1520 G02 X29. Z142.316 CR=691.139
N1050 X31.5
N1300 Z-145.603 F.7
N1530 G01 X30.131 Z141.751 F1.
N1060 G01 Z3. F.7
N1310 G02 X30.5 Z147.208 CR=691.139
N1540 G00 X30.5
gn
u.i
N1000 G01 Z3. F.7
N1250 G01 X32.131 Z148.223 F1.
N1070 Z-151.4 F.7
M.TECH (AMT)
N1490 X28.5
Page 42
CHAPTER-3
N1550 Z3.8
N1790 Z-133.584 F.7
N1560 X28.
N1800 G02 X27. Z135.396 CR=691.139
N1570 G01 Z3. F.7
N1590 G02 X28.5 Z140.632 CR=691.139
N1600 G01 X29.631 Z140.066 F1.
N1820 G00 X28.5
N1830 Z3.8
N1840 X26.
N1850 G01 Z3. F.7
N1620 Z3.8
N1860 Z-131.736 F.7
N1630 X27.5
N1870 G02 X26.5 Z133.584 CR=691.139
N1880 G01 X27.631 Z133.018 F1.
N1650 Z-137.173 F.7
N1670 G01 X29.131 Z138.352 F1.
N1680 G00 X29.5
N1900 Z3.8
N1910 X25.5
N1920 G01 Z3. F.7
N1930 Z-129.849 F.7
nfl
N1690 Z3.8
N1890 G00 X28.
ibn
N1660 G02 X28. Z138.918 CR=691.139
N1700 X27.
N1710 G01 Z3. F.7
u.i
N1720 Z-135.396 F.7
N1730 G02 X27.5 Z137.173 CR=691.139
gn
N1740 G01 X28.631 Z136.607 F1.
N1940 G02 X26. Z131.736 CR=691.139
N1950 G01 X27.131 Z131.17 F1.
N1960 G00 X27.5
N1970 Z3.8
N1980 X25.
N1750 G00 X29.
N1990 G01 Z3. F.7
N1760 Z3.8
N2000 Z-127.921 F.7
N1770 X26.5
N2010 G02 X25.5 Z129.849 CR=691.139
N1780 G01 Z3. F.7
M.TECH (AMT)
N2040 Z3.8
N2050 X24.5
N2060 G01 Z3. F.7
N2070 Z-125.949 F.7
N2080 G02 X25. Z127.921 CR=691.139
et.
a
N1610 G00 X30.
N1640 G01 Z3. F.7
N2030 G00 X27.
c.i
n
N1810 G01 X28.131 Z134.83 F1.
N1580 Z-138.918 F.7
N2020 G01 X26.631 Z129.283 F1.
N2090 G01 X26.131 Z127.355 F1.
N2100 G00 X26.5
N2110 Z3.8
N2120 X24.
N2130 G01 Z3. F.7
N2140 Z-123.93 F.7
N2150 G02 X24.5 Z125.949 CR=691.139
N2160 G01 X25.631 Z125.383 F1.
N2170 G00 X26.
N2180 Z3.8
N2190 X23.5
N2200 G01 Z3. F.7
N2210 Z-121.86 F.7
N2220 G02 X24.
123.93 CR=691.139
Z-
N2230 G01 X25.131 Z123.364 F1.
N2240 G00 X25.5
Page 43
CHAPTER-3
N2250 Z3.8
N2490 Z-112.988 F.7
N2260 X23.
N2500 G02 X22. Z115.305 CR=691.139
N2270 G01 Z3. F.7
N2510 G01 X23.131 Z114.739 F1.
N2290 G02 X23.5 Z121.86 CR=691.139
N2520 G00 X23.5
N2300 G01 X24.631 Z121.294 F1.
N2530 Z3.8
N2540 X21.
N2730
X20.112
106.123 F.7
N2740 G02 X20.5 Z108.114 CR=691.139
N2750 G01 X21.631 Z107.548 F1.
N2760 G00 X22.
N2310 G00 X25.
N2550 G01 Z3. F.7
N2320 Z3.8
N2560 Z-110.593 F.7
N2780 X19.5
N2330 X22.5
N2570 G02 X21.5 Z112.988 CR=691.139
N2790 G01 Z3. F.7
N2360 G02 X23. Z119.735 CR=691.139
N2590 G00 X23.
ibn
N2350 Z-117.552 F.7
N2580 G01 X22.631 Z112.422 F1.
N2370 G01 X24.131 Z119.17 F1.
N2380 G00 X24.5
N2400 X22.
N2410 G01 Z3. F.7
u.i
N2420 Z-115.305 F.7
N2430 G02 X22.5 Z117.552 CR=691.139
N2800 Z-103.039 F.7
N2810 G02 X20. Z105.567 CR=1114.218
N2600 Z3.8
N2820 G01 X21.131 Z105.001 F1.
N2610 X20.5
N2830 G00 X21.5
N2620 G01 Z3. F.7
N2840 Z3.8
N2630 Z-108.114 F.7
N2850 X19.
N2640 G02 X21. Z110.593 CR=691.139
N2860 G01 Z3. F.7
nfl
N2390 Z3.8
N2770 Z3.8
et.
a
N2340 G01 Z3. F.7
Z-
c.i
n
N2280 Z-119.735 F.7
N2720 G01 Z-106.122
F.7
N2650 G01 X22.131 Z110.028 F1.
N2660 G00 X22.5
N2870 Z-100.45 F.7
N2880 G02 X19.5 Z103.039 CR=1114.218
N2670 Z3.8
N2890 G01 X20.631 Z102.473 F1.
N2680 X20.
N2900 G00 X21.
N2450 G00 X24.
N2690 G01 Z3. F.7
N2910 Z3.8
N2460 Z3.8
N2700 Z-105.567 F.7
N2920 X18.5
N2470 X21.5
N2710 G02 X20.111 Z106.12 CR=1114.218
N2930 G01 Z3. F.7
gn
N2440 G01 X23.631 Z116.987 F1.
N2480 G01 Z3. F.7
M.TECH (AMT)
N2940 Z-97.796 F.7
Page 44
CHAPTER-3
N3180 G00 X19.
N3420 G01 Z3. F.7
N3190 Z3.8
N3430 Z-76.828 F.7
N2960 G01 X20.131 Z99.884 F1.
N3200 X16.5
N2970 G00 X20.5
N3210 G01 Z3. F.7
N3440 G02 X15.5 Z80.141 CR=1114.218
N2980 Z3.8
N3220 Z-86.407 F.7
N2990 X18.
N3230 G02 X17. Z89.383 CR=1114.218
N3000 G01 Z3. F.7
c.i
n
N2950 G02 X19. Z100.45 CR=1114.218
N3010 Z-95.071 F.7
N3470 Z3.8
N3480 X14.5
N3250 G00 X18.5
N3490 G01 Z3. F.7
N3260 Z3.8
N3500 Z-73.375 F.7
N3030 G01 X19.631 Z97.23 F1.
N3270 X16.
N3040 G00 X20.
N3280 G01 Z3. F.7
N3510 G02 X15. Z76.828 CR=1114.218
N3050 Z3.8
N3290 Z-83.33 F.7
N3060 X17.5
N3070 G01 Z3. F.7
N3080 Z-92.269 F.7
ibn
N3020 G02 X18.5 Z97.796 CR=1114.218
N3460 G00 X17.
et.
a
N3240 G01 X18.131 Z88.818 F1.
N3450 G01 X16.631 Z79.575 F1.
N3310 G01 X17.631 Z85.841 F1.
N3530 G00 X16.5
N3540 Z3.8
N3550 X14.
N3320 G00 X18.
N3560 G01 Z3. F.7
N3330 Z3.8
N3570 Z-69.762 F.7
N3100 G01 X19.131 Z94.505 F1.
N3340 X15.5
N3110 G00 X19.5
N3350 G01 Z3. F.7
N3580 G02 X14.5 Z73.375 CR=1114.218
N3120 Z3.8
N3360 Z-80.141 F.7
N3590 G01 X15.631 Z72.809 F1.
N3130 X17.
N3370 G02 X16. Z-83.33
CR=1114.218
N3600 G00 X16.
u.i
nfl
N3090 G02 X18. Z95.071 CR=1114.218
N3300 G02 X16.5 Z86.407 CR=1114.218
N3520 G01 X16.131 Z76.262 F1.
gn
N3140 G01 Z3. F.7
N3150 Z-89.383 F.7
N3160 G02 X17.5 Z92.269 CR=1114.218
N3170 G01 X18.631 Z91.703 F1.
M.TECH (AMT)
N3380 G01 X17.131 Z82.764 F1.
N3610 Z3.8
N3620 X13.5
N3390 G00 X17.5
N3630 G01 Z3. F.7
N3400 Z3.8
N3640 Z-65.966 F.7
N3410 X15.
Page 45
CHAPTER-3
N3650 G02 X14. Z69.762 CR=1114.218
N3660 G01 X15.131 Z69.197 F1.
N3880 Z-55.007 F.7
N3890 G02 X12.5 Z57.689 CR=1114.218
N3680 Z3.8
N3910 G00 X14.
N3690 X13.
N3920 Z3.8
N3700 G01 Z3. F.7
N3930 X11.5
N3710 Z-61.956 F.7
N3940 G01 Z3. F.7
N3720 G02 X13.5 Z65.966 CR=1114.218
N3950 Z-48.783 F.7
N3960 G02 X12. Z53.249 CR=1939.323
N3750 Z3.8
N3980 G00 X13.5
N3770 G01 Z3. F.7
N3780 Z-57.689 F.7
ibn
N3740 G00 X15.
N3970 G01 X13.131 Z52.683 F1.
N3760 X12.5
N3990 Z3.8
N4000 X11.
N4010 G01 Z3. F.7
N4020 Z-44.119 F.7
nfl
N3790 G02 X13. Z61.956 CR=1114.218
N3800 G01 X14.131 Z61.39 F1.
N4030 G02 X11.5 Z48.783 CR=1939.323
N3820 Z3.8
N4050 G00 X13.
N3830 X12.
N4060 Z3.8
N3840 G01 Z3. F.7
N4070 X10.5
gn
u.i
N3810 G00 X14.5
N4040 G01 X12.631 Z48.217 F1.
N3850 Z-53.249 F.7
N4080 G01 Z3. F.7
N3860 G02 X12.202 Z55.004 CR=1939.323
N4090 Z-39.23 F.7
N3870 G01 Z-55.005 F.7
M.TECH (AMT)
N4130 Z3.8
N4140 X10.
N4150 G01 Z3. F.7
N4160 Z-34.08 F.7
N4170 G02 X10.5 Z39.23 CR=1939.323
et.
a
N3730 G01 X14.631 Z65.401 F1.
N4120 G00 X12.5
c.i
n
N3670 G00 X15.5
N3900 G01 X13.631 Z57.124 F1.
N4110 G01 X12.131 Z43.554 F1.
N4100 G02 X11. Z44.119
CR=1939.323
N4180 G01 X11.631 Z38.665 F1.
N4190 G00 X12.
N4200 Z3.8
N4210 X9.5
N4220 G01 Z3. F.7
N4230 Z-28.621 F.7
N4240 G02 X10. Z-34.08
CR=1939.323
N4250 G01 X11.131 Z33.514 F1.
N4260 G00 X11.5
N4270 Z3.8
N4280 X9.
N4290 G01 Z3. F.7
N4300 Z-22.79 F.7
N4310 G02 X9.5 Z28.621 CR=1939.323
N4320 G01 X10.631 Z28.055 F1.
N4330 G00 X11.
Page 46
N4340 Z3.8
N4350 X8.5
N4360 G01 Z3. F.7
N4530 G01 X9.131 Z9.053 F1.
N4710 G03 X6.014 Z1.019 CR=1.05
N4540 G00 X9.5
N4720 G02 X10.802 Z55.503 CR=1939.323
N4550 Z.566
N4380 G02 X9. Z-22.79
CR=1939.323
N4390 G01 X10.131 Z22.224 F1.
N4400 G00 X10.5
N4730 G01 Z-55.507 F.3
N4560 X8.514
N4570 G01 X7.383 Z0.0
F.7
N4580 X7.399
F.7
Z-.276
N4590 G02 X7.5 Z-1.945
CR=1939.323
N4410 Z3.8
N4420 X8.
N4440 Z-9.619 F.7
N4610 G00 X33.435
N4450 G02 X8.5 Z16.499 CR=1939.323
N4620 Z-150.93
N4460 G01 X9.631 Z15.933 F1.
N4640 G01 X31. F.7
N4650 X30.739 Z-151.4
F.5
N4630 X32.6
N4660
X31.871
150.834 F1.
Z-
N4770 G03 X29.913 Z150.35 CR=1.05
Z-
N4800 G02 X29.294 Z151.828 CR=1.6 F1.
N4810
153.369
CR=1.6
X31.638
Z-
N4670 G00 X65.394
N4820 G00 X56.632
N4680 Z15.653
N4830 Z12.555
N4690 X.715 Z1.6
N4840 G00 X100. Z100.
N4700 G02 X3.915 Z0.0
CR=1.6 F.3
N4850 M05 M09
N4500 G01 Z3. F.7
N4510 Z-1.945 F.7
u.i
N4760 G02 X29.886 Z150.183 CR=691.139
N4790 G01 X29.41 Z 151.4 F.3
N4490 X7.5
N4860M30
gn
N4520 G02 X8. Z-9.619
CR=1939.323
N4750 G01 X18.712 Z106.624 F.3
N4780
X29.837
150.631 CR=1.05
nfl
N4480 Z3.8
ibn
N4430 G01 Z3. F.7
N4600 G01 X8.631 Z1.38 F1.
N4470 G00 X10.
N4740 G02 X18.711 Z106.619 CR=1114.218
et.
a
N4370 Z-16.499 F.7
c.i
n
CHAPTER-3
M.TECH (AMT)
Page 47
gn
u.i
nfl
ibn
et.
a
c.i
n
CHAPTER-3
M.TECH (AMT)
Page 48
gn
u.
inf
lib
ne
t.a
c.i
n
CHAPTER-3
M.TECH (AMT)
Page 49
CHAPTER-4
DESIGN OF EXPERIMENT
4.1 Introduction
In DOE, we deliberately change one or more process variables (or factors) in order to
observe the effect the changes have on one or more response variables. The (statistical)
c.i
n
design of experiments (DOE) is an efficient procedure for planning experiments so that the
data obtained can be analyzed to yield valid and objective conclusions.
DOE begins with determining the objectives of an experiment and selecting the process
factors for the study. An Experimental Design is the laying out of a detailed experimental
plan in advance of doing the experiment. Well chosen experimental designs maximize the
4.2 Methods of DOE
et.
a
amount of "information" that can be obtained for a given amount of experimental effort.
Following methods are used in design
1) Taguchi method
2) Factorial method
3) Response surface method
4.3 Selection of Parameters &Experiment Plan
ibn
From the literature review, mostly work done on parameters like pressure, amplitude,
thickness, time, clamping force. Range for pressure is between 2 to 4bar and thickness is
about up to 5 to 6 mm and amplitude range is 0.7 to 0.9µm,from that, parameters like
pressure, thickness ratio (0.75,1,1.5mm) and sonotrode (horn) are selected as control
parameters because of our experiment set up limit in our set up we can change only
nfl
amplitude, pressure, time. Tensile strength selected as response parameter.
To save time and cost, Taguchi method was selected for this study. Dr. Taguchi of Nippon
Telephones and Telegraph Company, Japan has developed a method based on “Orthogonal
u.i
Array” experiments which gives much reduced “variance” for the experiment with optimum
settings of control parameters. “Orthogonal Arrays” provide a set of well balanced
experiments. Signal-to-Noise ratios, which are log function of desired output, serve as
objective functions for optimization, help in data analysis and prediction of optimum results.
gn
4.4 Input Parameters
1) Factor A: Horn type
2) Factor B: pressure (bar)
3) Factor C: Thickness ratio(mm)
M.TECH (AMT)
Page 48
CHAPTER-4
Table 4.1 Factor with levels value
Level 1
Taper
2
0.75
Level 2
Step-cylindrical
3
1
Level 3
Exponential
4
1.5
c.i
n
Factors
Horn
Pressure
Thickness ratio
DESIGN OF EXPERIMENT
As per table, we select L9 orthogonal array for each combination of design for 3 factors and
3 levels with 9 runs as shown in Table
Table 4.2 Experiment Runs
Sr
No
Horn
Taper
2
Taper
Thickness
ratio(mm)
2
0.75
3
1
Taper
4
1.5
4
Step-cylindrical
2
0.75
5
Step-cylindrical
3
1
nfl
3
Pressure(bar)
ibn
1
et.
a
Input parameter
Step-cylindrical
4
1.5
7
Exponential
2
0.75
u.i
6
8
Exponential
3
1
9
Exponential
4
1.5
gn
4.5 Output Parameters
Weld Tensile strength
M.TECH (AMT)
Page 49
CHAPTER-5
EXPERIMENT SET-UP
Our task is to investigate the effects of horn profile and other parameters like pressure and
thickness ratio on welding strength (tensile) of HDPE (High-Density polyethylene) plastic
using ultrasonic welding machine. This can possible by performing exclusive experiments
u.i
nfl
ibn
et.
a
c.i
n
as per DOE, L9 orthogonal at M.S. UNIVERSITY BARODA.
Figure: 5.1 Machine setup in Laboratory
5.1 Specification of ultrasonic welding machine
gn
Model - Usp 2500
Power - 2 KW
Frequency – 20 kHz
Head travel – 250 mm
Tool travel - 100 mm
M.TECH (AMT)
Page 50
CHAPTER-5
EXPERIMENT SET-UP
gn
u.i
nfl
ibn
et.
a
c.i
n
5.2 Generator controller
Figure: 5.2. Generator controller
The unit shown above is required to change and regulate the parameters like frequency and
amplitude of the USWM. Along with that it also monitors the power load of the machine
while the welding process. As it shows above there is an option for tuning the concentrator
in two frequencies that are 20 kHz and 36 kHz. The amplitude can be varied from 70 % to a
100% of the total permissible amplitude.
M.TECH (AMT)
Page 51
CHAPTER-5
ibn
et.
a
c.i
n
5.3 Transducer and Concentrator
EXPERIMENT SET-UP
nfl
Figure: 5.3 Transducer and concentrator with tool holder and tool
The above figure shows the assembly of the transducer, concentrator, tool holder and the
tool. The titanium alloy transducer is connected to the concentrator that is made up of
aluminum. The titanium alloy transducer is advantageous because of being corrosion
u.i
resistance and due to its high resistance to electrical and mechanical noise of pumps etc. The
concentrator is under constant mechanical force that causes it to be heated up quite quickly.
Here comes the application of aluminium as the right material for a concentrator. A cooling
system is placed near the transducer to prevent excessive heating by supplying pressurized
gn
air around the transducer cabinet.
M.TECH (AMT)
Page 52
CHAPTER-5
EXPERIMENT SET-UP
ibn
et.
a
c.i
n
5.4 Air Compressor, Fixture and Tensile Testing Machine
Figure: 5.4 Air compressors
In above figure shows air compressor which is use for produces pressure to hold the work
piece after energy transfer phase is completed. Its creates up to 10 Kbar pressure and
gn
u.i
nfl
ultrasonic welding machine require only up-to 4 to 5 bar pressure.
Figure: 5.5 Fixture
M.TECH (AMT)
Page 53
CHAPTER-5
EXPERIMENT SET-UP
Fixture is used to fix the work piece against horn and pressure of system. Fixture was design
ibn
et.
a
c.i
n
as per work piece dimension.
nfl
Figure: 5.6 Tensile testing machine
In above fig shows instron 1121 tensile testing machine for plastic material, its limit is about
1000 kg.
Table 5.1 About tensile testing machine
Instron 1121
Application
Plastic tests
gn
u.i
Type
M.TECH (AMT)
Retrofit
EDC120
Specials
Video extensometer for strain measurement
Page 54
CHAPTER-5
EXPERIMENT SET-UP
By using this set-up, prepared 9 samples for testing tensile strength to investigate effect of
horn profile on welding strength of HDPE plastic. A properties of HDPE is under
c.i
n
Table 5.2 Properties of HDPE [29]
Properties
Value
Density (g/cm3)
0.96
15
Tensile Strength (MPa)
Surface Hardness
et.
a
Strain at Yield (%)
32
SD68
220 - 310
ibn
Melting Temp. Range (°C)
Table 5.3 sample number and values
Number
Taper horn
nfl
1
Values
Step-cylindrical horn
3
Exponential horn
u.i
2
2 bar pressure & 0.75mm Thickness ratio
B
3 bar pressure & 1mm Thickness ratio
C
4 bar pressure & 1.5 mm thickness ratio
gn
A
M.TECH (AMT)
Page 55
EXPERIMENT SET-UP
ibn
et.
a
c.i
n
CHAPTER-5
gn
u.i
nfl
Figure: 5.7 Samples of conical horn before testing
M.TECH (AMT)
Figure: 5.8 Samples of step-cylindrical horn before testing
Page 56
EXPERIMENT SET-UP
ibn
et.
a
c.i
n
CHAPTER-5
gn
u.i
nfl
Figure: 5.9 Samples of exponential horn before testing
M.TECH (AMT)
Figure: 5.10 Samples of conical horn after testing
Page 57
EXPERIMENT SET-UP
et.
a
c.i
n
CHAPTER-5
gn
u.i
nfl
ibn
Figure: 5.11 Samples of step-cylindrical horn after testing
M.TECH (AMT)
Figure: 5.12 Samples of exponential horn after testing
Page 58
CHAPTER-6
RESULT AND DISCUSSION
6.1 Comparison of Design Results with CARD Output
As discussed earlier, CARD is software to generating and analyzing different sonotrodes
under varying working conditions. Data of diameters and resonance length calculated from
c.i
n
theoretical method are supplied to CARD to generate design result of concern sonotrode
shape profile. Table 3.2 shows the comparison of theoretical and CARD software results.
It can be observed that for the same input conditions, there is very little variation in the
sonotrode design result. The Transformation ratio of horn by using CARD software and by
using theoretical equation is closer. Hence CARD software may be useful tool for horn
et.
a
design.
Table 6.1 Tensile Testing Results of 9 Samples
Input parameter
Sr
No
Pressure (bar)
Thickness ratio
ibn
Horn
Measured response
Taper
2
0.75
6.07
2
Taper
3
1
8.18
3
Taper
4
1.5
11.47
4
Step-cylindrical
2
0.75
5.64
5
Step-cylindrical
3
1
7.62
6
Step-cylindrical
4
1.5
10.82
7
Exponential
2
0.75
6.99
8
Exponential
3
1
8.32
4
1.5
12.41
gn
u.i
nfl
1
Tensile strength
(N/mm²)
9
Exponential
M.TECH (AMT)
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CHAPTER-6
6.2 Tensile strength VS. Pressure & Thickness ratio
Tensile srength Vs. Thickness ratio & Pressure for Conical Horn
12
11.47
10
8.18
8
Tensile srength
(N/mm²)
6
6.07
Tensile srength
2
0
0.75
Pressure
2
et.
a
4
Thickness ratio
c.i
n
14
1
1.5
3
4
Thickness ratio & Pressure (bar)
ibn
Figure: 6.1 Graph of Tensile Strength Vs. Thickness ratio & pressure For Sample
Prepared by Conical Horn
Tensile srength Vs. Thickness ratio & Pressure for Stepcylindrical Horn
nfl
12
10.82
10
8
Tensile srength
6
(N/mm²)
7.62
Tensile srength
u.i
5.64
4
2
gn
Thickness ratio
Pressure
0
0.75
1
1.5
2
3
4
Figure: 6.2 Graph of Tensile Strength Vs. Thickness ratio & pressure For Sample
Prepared by Step-Cylindrical Horn
M.TECH (AMT)
Page 60
CHAPTER-6
14
12.41
12
10
Tensile
srength 8
(N/mm²) 6
8.32
6.99
2
Pressure
0.75
2
Tensile srength
et.
a
4
0
Thickness ratio
c.i
n
Tensile srength Vs. Thickness ratio & Pressure for
Exponential Horn
1
1.5
3
4
ibn
Figure: 6.3 Graph of Tensile Strength Vs. Thickness ratio & Pressure for Sample
Prepared by Exponential Horn
From Fig 6.1 in which tensile strength Vs. pressure & thickness ratio for three sample
prepared by the conical horn. Result shows that the tensile weld strength of material is
nfl
higher at 3 bar pressure and 1.5 thickness ratio and lower at 2 bar pressure and 0.75
thickness ratios. In this tensile strength is increase with increase the pressure. It shows that
tensile strength increase with increase the thickness ratio also. For the conical horn sample,
tensile strength at 2 bar pressure & 0.75 thickness ratio is 6.07 N/mm². When the pressure is
u.i
increase 1bar and thickness ratio is increase 0.25 the tensile strength is also increase up to
8.18 N/mm². If further increase of pressure 1 bar and ratio is 0.5 the tensile strength is
increase up to 11.47 N/mm². So that the highest tensile strength value for conical horn is
11.47 N/mm² and lowest value is 6.07 N/mm²
gn
From the Fig.6.2 in which tensile strength Vs. pressure & thickness ratio for three sample
prepared by the step-cylindrical horn. Result shows that the tensile weld strength of material
is higher at 3 bar pressure and 1.5 thickness ratio and lower at 2 bar pressure and 0.75
tensile strength increase with increase the thickness ratio also. For the step-cylindrical horn
sample, tensile strength at 2 bar pressure & 0.75 thickness ratio is 5.64 N/mm². When the
pressure is increase 1bar and thickness ratio is increase 0.25 the tensile strength is also
M.TECH (AMT)
Page 61
CHAPTER-6
increase up to 7.62 N/mm². If further increase of pressure 1 bar and ratio is 0.5 the tensile
strength is increase up to 10.819 N/mm². So that the highest tensile strength value for
conical horn is 10.82 N/mm² and lowest value is 5.64 N/mm².
c.i
n
From Fig.6.3 in which tensile strength Vs. Pressure & thickness ratio for three sample
prepared by the exponential horn. Result shows that the tensile weld strength of material is
higher at 3 bar pressure and 1.5 thickness ratio and lower at 2 bar pressure and 0.75
tensile strength increase with increase the thickness ratio also. For the conical horn sample,
tensile strength at 2 bar pressure & 0.75 thickness ratio is 6.99 N/mm². When the pressure is
et.
a
increase 1bar and thickness ratio is increase 0.25 the tensile strength is also increase up to
8.32 N/mm². If further increase of pressure 1 bar and ratio is 0.5 the tensile strength is
increase up to 12.41 N/mm². So that the highest tensile strength value for conical horn is
12.41 N/mm² and lowest value is 6.99 N/mm².
6.2.1 Discussion
6.2.1.1 Pressure
ibn
The following may be the reasons for the above result.
In case of ultrasonic plastic welding the pressure is generated by pneumatic cylinder that is
applied to entire transducer, booster, and sonotrode assembly.
Once the vibration energy is applied or transfer to material at the joint location. Now force
nfl
generated by pneumatic cylinder comes in to picture. Because of this pressure, the atoms
which are free by the energy transfer phase entering from one surface to gaps between
atoms of other surface. As consolidate welding strength with increase in pressure at the joint
location by causing deeper inter surface penetration of the atoms.
u.i
Simply the role of pressure come in action after the phase of energy transfer is completed
means that when the operation starts the transducer converts the electrical signal to
mechanical vibration that is transfer to the work piece surface through booster and horn.
Horn is amplified the vibration at the work piece surface. Because of this large amplitude
gn
the heat is generated and energy transfer from one surface to another surface by the action
of atoms. At this stage because of increment in pressure large force is produced and two
surfaces come in contact. If pressure is further increase then more atoms are transfer from
one surface to gaps between atoms of other surface at that time wan-der-val attraction is
done so strong bonding is possible and tensile strength is increase also.
M.TECH (AMT)
Page 62
CHAPTER-6
6.2.1.2 Thickness ratio
It is also important factor in ultrasonic welding. Generally the thickness ratio is small means
transferring the energy.
c.i
n
that the thickness of upper surface is smaller than the bottom surface is good for the
In case of ultrasonic plastic welding the vibration comes from the horn is transfer from one
surface to other surface. So, if upper surface thickness is small then its transfer more energy
compare with bigger surface. If thickness is small, more energy is transfer from one surface
to other surface. But only energy transfer is not enough for producing the better bonding, for
better bonding the pressure is require. It means that at the constant pressure the welding
et.
a
strength is increase with decreasing the thickness ratio.
But in this study the tensile strength is increase with increasing the thickness ratio. Because
in this study when the thickness ratio is increase pressure is also increase so that tensile
strength is increase instead of decrease. Its means that pressure is more affected to tensile
strength then the thickness ratio. Shown in fig.6.1, 6.2, and 6.3 the tensile strength Vs.
Thickness ratio graph the tensile strength is increase with increasing the thickness ratio
ibn
because of pressure. In fig tensile strength at 0.75 thickness ratio is lower than at 1.5
thickness ratio, because of at 0.75 thickness ratio pressure is 2bar and at 1.5 thickness ratio
the pressure is 4 bars. Pressure is more affected factor than thickness ratio.
6.3 Comparison of different horn value
nfl
Tensile srength Vs. Thickness ratio & Pressure of three different
horn
14
12
10
6.99
6.07
u.i
Tensile srength
8
(N/mm²)
6
4
12.41
11.47
8.32
8.18
10.82
Step-cylindrical
5.64
2
Exponential
0
gn
Thickness ratio
Pressure
conical
7.62
0.75
1
1.5
2
3
4
Figure: 6.4 Graph of Tensile Strength Vs. Thickness ratio & Pressure of three
Different Horn
M.TECH (AMT)
Page 63
CHAPTER-6
In fig.6.4 shows that the exponential shape horn produced higher tensile strength at any
value of pressure and thickness ratio. The conical shape produced tensile strength which is
c.i
n
more than step-cylindrical and less than exponential tensile strength at any value of pressure
and thickness ratio. Step-cylindrical horn produced lowest strength. When the pressure is
increase then tensile strength also increase for all type of horn shape.
Exponential horn produced highest tensile strength for HDPE plastic at 4 bar pressure and
1.5 thickness ratio is 12.41 N/mm², at that time tensile strength of conical and stepcylindrical horn is 11.47 N/mm² and 10.82 N/mm².
et.
a
Step-cylindrical horn produced lowest tensile strength for HDPE plastic at 2 bar pressure
and 0.75 thickness ratio is 5.64 N/mm², at that time tensile strength of exponential and
conical horn is 6.99 N/mm² and 6.07 N/mm².
6.3.1 Discussion
Horn is important factor or tool which is affect the tensile strength, it is amplified the
vibration, a horn which has large transformation ratio or gain produced large amplitude at
ibn
the end of horn at work piece surface. If the amplitude is large, more heat is generated so
that surface become a more soft and more atoms is free from its position so that
displacement of atoms is more and so that the propagation of wave is very fast, more energy
is transfer. It means that when the pressure and thickness ratio keep constant and experiment
done with change only horn then tensile strength is depend on only amplitude generated by
nfl
horn, more amplitude has more tensile strength.
In this study exponential horn produced more amplitude compare conical and stepcylindrical horn, conical horn produced more amplitude than step-cylindrical and less than
u.i
exponential. So that exponential produced more tensile strength.
6.4 Problem face in step-cylindrical design
Generally in step-cylindrical horn, step provided at middle of the length. In this work first
gn
create this type of design in CARD software, results are CARD software is below.
M.TECH (AMT)
Page 64
ibn
et.
a
c.i
n
CHAPTER-6
gn
u.i
nfl
Figure: 6.5 Stress diagram for step-cylindrical shaped sonotrode profile
Figure: 6.6 CARD result for step-cylindrical shaped sonotrode profile
M.TECH (AMT)
Page 65
CHAPTER-6
But result shows that this type of design produced more transformation ratio about 22.97,
because of end diameter is very small compare bigger diameter. High transformation ratio
produced high amplitude and high stress also. Because of large amplitude large heat is
c.i
n
generated which melt the entire upper surface of work piece so weld quality is not good and
some time welding is not possible but in metal welding it is very used for good result.
So that for this dissertation, prepares the different design shown in fig 3.4 and 3.5 for HDPE
plastic. Its gain is 1.16 and it is produced low amplitude but with the help of this type of
gn
u.i
nfl
ibn
et.
a
horn welding of HDPE plastic is possible.
M.TECH (AMT)
Page 66
CHAPTER-7
CONCLUSION
Conclusion
From the above discussion it is evident that under the condition of same area ratio between
its’ two ends Cross sections the transformation ratio of them is in descending order for the
c.i
n
exponential shape, conical shape and step-cylindrical shape respectively. A stepped shape
horn produced lower amplitude, since it produced low strength. Tensile strength results
show that for ultrasonic plastic welding, conical shaped horn and exponential shaped horn
are better than step-cylindrical shape horn.
Where manufacturing cost and time is important parameters exponential shape horn is rarely
et.
a
use because of cost of manufacturing & design of horn is more costly compare to other type
horn have near to same amplitude and gain Conical horn shape is easy to manufacture and
also has almost nearest amplitude as exponential shape horn. Therefore, conical shaped horn
is extensively used in industry.
However, it can be clearly observed that both values calculated by theoretical equation are
slightly exceeding the values by CARD software. From above results one can conclude that
transformation ratio or gain of horn by using CARD software and by using theoretical
gn
u.i
nfl
ibn
equation is closer. Hence CARD software may be useful tool for horn design.
M.TECH (AMT)
Page 67
CHAPTER-8
FUTURE SCOPE
Future scope
1) The current work was done for three types of sonotrode shape profiles. This work
c.i
n
also carried out with other shape profiles or combinations of shape profiles.
2) The current work was done for half wave length resonant length. This work also
carried out for the resonant length of multiple of half wave length.
3) The current work was done for HDPE plastic. This work also carried out with
different material and with metal material also.
4) The current work was done using EN24 horn material; work will extend using
gn
u.i
nfl
ibn
et.
a
different horn material.
M.TECH (AMT)
Page 68
CHAPTER-9
REFERENCES
References
1. K.C.Srivastava, Hand book of ultrasonic testing, published by International-2001(page
c.i
n
no.1).
2. Peter B. Nagy, INTRODUCTION TO ULTRASONICS-2001(page no-1-2,1-7)
3. Johannes Leendert tharthoon, book of ultrasonic metal welding (page no-2,3)
4. Al-Sarraf, Ziad Shakeeb (2013), A PhD thesis on study of ultrasonic metal welding.
5. Deven Dhirajlal Pandya (2013), a thesis on CAD/CAM/CAE of Sonotrode using in
ultrasonic machine, MSU, Baroda.
ne
t.a
6. Tao Li, Jan Ma and Adrian F. Low, Horn-Type Piezoelectric Ultrasonic Transducer:
Modeling and Applications.
7. Sunil K. Patel, A thesis on Experimental investigation and Parametric characteristics of
an Ultrasonic Plastic Welding for ABS, Polycarbonate and Acrylic material, Ganpat
University.
8. A. Dipal M. Patel, B. Avadhoot U. Rajurkar, Analysis of Different Shaped Sonotrodes
used for Plastic Welding
Ahmadabad – 2011.
Published
in institute of technology, nirma university,
u.
inf
lib
9. M. Roopa Rani, R. Rudramoorthy, Computational modeling and experimental studies of
the dynamic performance of ultrasonic horn profiles used in plastic welding Published
in Ultrasonics 53 (2013).
10. Eng. Alexandra sergiu nanu, prof. Niculae ion marinescu, Assoc. Prof. Daniel
ghiculescu, Study on ultrasonic stepped horn geometry Design and fem simulation
published in Nonconventional Technologies Review – no. 4/2011.
11. Kuen-Ming Shu*, Hsieh, Wen- Hsiang, The design of acoustic horns for ultrasonic
insertion published in National Formosa University-2002.
12. M. Nad’ Ultrasonic horn design for ultrasonic machining technologies published in
Applied and Computational Mechanics 4 (2010).
gn
13. Nad, M.; Cicmancova, L. The effect of the shape parameters on modal properties of
ultrasonic horn design for ultrasonic assisted machining published in 8th International
daaam Baltic Conference industrial engineering 2012.
14. Hai-Dang Tam Nguyen, Dung-An Wang, design of an ultrasonic steel horn with a
Bezier profile published in International Conference on Green Technology and
Sustainable Development September 29-30, 2012.
M.TECH (AMT)
Page 69
CHAPTER-9
REFERENCES
15. j.pradeep kumar & k.prakasan, Experimental studies on joining copper wire - copper
sheet Using ultrasonic metal welding published in published in International Journal of
Mechanical and Production Engineering Research and Development (IJMPERD) 2012.
c.i
n
16. Shin-ichi Matsuokaa, Hisashi Imaib, Direct welding of different metals used ultrasonic
vibration published in journal of materials processing technology 2 0 9 (2009).
17. T.H. Kim a, J. Yuma, S.J. Hu , J.P. Spicer , J.A. Abell, Process robustness of single lap
ultrasonic welding of thin, dissimilar materials published in CIRP Annals Manufacturing Technology 60 (2011).
ne
t.a
18. S Elangovan, S Venkateshwaran 2, K Prakasan, Eexperimental investigations on
optimization of Ultrasonic welding parameters for copper to Brass joints using response
surface method and Genetic algorithm published in International Journal of Advanced
Engineering Research and Studies (2012).
19. Marius pop-calimanu, dinu gubencu, Ioana pop-calimanub, Traian fleser, Optimization
of ultasonic welding parameters and temperature distribution in metal matrix composite
based on aluminium Published in University of Timisoara (2013).
20. TakehikoWatanabe, Hideo Sakuyama, Atsushi Yanagisawa, Ultrasonic welding
u.
inf
lib
between mild steel sheet and Al–Mg alloy sheet Published in Journal of Materials
Processing Technology 209 (2009).
21. http://static.ddmcdn.com/gif/ultrasonic-welding-1.gif
22. http://www.mpi-ultrasonics.com/images/standard-horn-line.jpg
23. Harsha s.Guhe A thesis on FDM and FEM of velocity horn of ultrasonic machine, The
M.S. University of Baroda.
24. Iulian Stǎnǎşel, Flavius Ardelean, The parametric design of the ultrasonic exponential
horns, in Nonconventional Technologies Review – no. 4/2010.
25. I. Fernandez, D. Stavrov, H.E.N. Bersee, Ultrasonic welding of advanced Thermoplastic
composites: an investigation on energy directing surfaces in Delft University of
Technology Kluyverweg 1, 2629 HS Delft.
gn
26. W. Michaelia, E. Haberstrohb, W.-M. Hoffmann, Ultrasonic welding of micro plastic
parts, in Institute of Plastics Processing (IKV), RWTH Aachen University, Aachen,
Germany.
27. Rozenberg, L.D., V.F. Kazantsev, L. O. Makarov and D.F. Yakhimovich, Ultrasonic
Cutting published in Consultants Bureau,1964.
M.TECH (AMT)
Page 70
CHAPTER-9
REFERENCES
28. file:///H:/study/Dp-1/AISI%204340%20Alloy%20Steel%20(UNS%20G43400).htm
gn
u.
inf
lib
ne
t.a
c.i
n
29. http://www.azom.com/article.aspx?ArticleID=421
M.TECH (AMT)
Page 71

EFFECT OF HORN (SONOTRODE) PROFILE ON WELD

Transcription

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