Slayt 1

HISTORY OF MATERIALS
Yrd. Doç. Dr. Hülya KAFTELEN
Mühendislik malzemesi nedir?
• Mühendislik ürün ve sistemlerin imalinde kullanılan ve mekanik,
fiziksel ve kimyasal olarak istenilen özelliklere sahip katılardır.
Malzeme Bilimi nedir?
• Malzemelerin bileşim, yapı ve özellikleri arasındaki ilişkileri
bunların kimyasal, mekanik ve ısıl işlemle değişimlerini
inceleyerek çeşitli kullanım alanlarına göre mevcut malzemelerin
özelliklerini ve yeni malzemeler oluşturulmasını sağlayacak
üretim yöntemlerini geliştiren önemli bir bilim dalıdır.
Malzeme Mühendisliği nedir?
• Malzeme biliminin sunduğu yapı ve özellik arasındaki bilgiye
dayanarak, arzu edilen özellikte malzemelerin tasarlanması
ve imal edilmesidir.
Common materials: with various ‘viewpoints’
Graphite
Glass: amorphous
Ceramics
Crystal
Metals
Polymers
Historical Perspective
Stone → Bronze → Iron → Advanced materials
• Beginning of the Material Science - People began to make
tools from stone – Start of the Stone Age about two million
years ago.
Natural materials: stone, wood, clay, skins, etc.
The Stone Age ended about 5000 years ago with introduction
of Bronze in the Far East.
• Bronze is an alloy (a metal made up of more than one
element), copper + < 25% of tin + other elements.
Bronze: can be hammered or cast into a variety of shapes, can
be made harder by alloying, corrode only slowly after a
surface oxide film forms.
Historical
• The Iron Age began about 3000 years ago and continues today. Use
of iron and steel, a stronger and cheaper material changed
drastically daily life of a common person.
• Age of Advanced materials: throughout the Iron Age many new
types of materials have been introduced (ceramic, semiconductors,
polymers, composites…). Understanding of the relationship among
structure, properties, processing, and performance of materials.
Intelligent design of new materials.
1200BC - Earliest quenching and tempering of steel to harden it. Steel is
an alloy of Fe and C. This began in Greece. Homer refers to this process
in his Odyssey, describing the blinding of Cyclops.
900 BC - Hardened steel tools & weapons were in widespread use,
displacing the older bronze technology.
1903 - Precipitation hardening of Al, the first nano-technology. This
process is often referred to as age hardening. The Wright Bros. used an
alloy of Al + 8wt% Cu for the engine in their plane. Fe engines were too
heavy to get off the ground. Similar Al-Cu alloys have been used
extensively in the aircraft industry ever since, for the main structure and
skin of the aircraft. In the literature you will often see this discovery
attributed to Alfred Wilm who published a paper on the subject in 1911
and received a patent.
Automobile axles
The Materials Tetrahedron
Wings of plane
Historical
Understanding the structure-composition-properties lead to a remarkable
progress in properties of materials. e.g. the strength : density ratio of
materials, resulted in a variety of new products, from dental materials to
tennis racquets.
Seramik malzemelerin tarihçesi
Seramik malzemeler ateşin bulunmasından sonraki tarihlerde yapılmaya başlanmıştır. İlk
seramik, MÖ 9000 ve 10000 yıl öncesine dayanmaktadır. En eski seramik buluntulara
Türkistan Aşkava bölgesinde (MÖ 8000), Filistin ‘in Jericho bölgesinde (MÖ 7000) ve
Mezopotamyada dicle ve fırat nehirleri arasında rastlanmıştır.
Seramiklerin sırlanması, MÖ 5000-6000 yıllarında odun ve benzeri organik maddelerin
küllerinin seramik çamurunun üzerine etkilerinin gözlenmesi sonucu keşfedilmiştir.
Seramik malzemelerin tarihçesi
 Yunanistanda seramik üreten çömlekçilere “kerameus” bu çömlekçilerin eski Atina’da toplu
olarak oturdukları bölgeye de “keramikos” adı verildi.
İlk seramik ürünler, çanak-çömlek türünden kaplardır.
Mezopotamya ve iran’da özellikle Mısır’da Nil nehri balçığından yapılma tuğlalar, Babil’de
üzerine yazı yazılan kil tabletler, seramik ürünlerin ilginç örneklerini oluşturmaktadır.
 Osmanlılarda çini sanatı 16. yy’da İznikteki çok sayıda kurulmuş atölyelerle, Bursa ve
İstanbul’un ünlü Osmanlı yapılarını süslemiştir.
 Bugün tek bir atölye bile kalmamış olan İznikten, Kütahya ve 18.yy da da Çanakkale
bölgelerinde seramik merkezleri kurulmuştur.
 9.yy da ispanya ve italya ve diğer Avrupa ülkelerinde yayınlaşmıştır.
 Ortaçağda italya’nın Feanza kentinde üretilen seramiklere, günümüzde kullanılan ‘fayans’
adı verilmiştir.
 1710 yılında Almanya Meissen kentinde ilk porselen fabrikası kurulmuştur.
 Porselen kelimesi latincede bir tür kabuklu deniz hayvanının (istridye) kabuğunun ‘porsella’
olan isminden gelmektedir.
Türkiye’de ilk kurulan (1982 yılında) porselen ve çini fabrikası Yıldız porselendir. Türkiye’de
seramik sektör gerçek anlamda 1960 yıllarında Eczacıbaşı ve Çanakkale seramik girişimleri ile
başlamıştır.
Uygulama alanları
Uygulama alanları
Shafts and Valves
Pump Parts
Uygulama alanları
Hip implants
Advantages of Ceramics
•Low friction
•Biocompatibility
•Compressive strength
http://ceramics.org/ceramictechtoday/tag/capacitor/
http://www.amjorthopedics.com/html/new/0605.asp
HISTORY OF PLASTICS
Charles Goodyear
Charles Goodyear spent most of his adult life trying to improve the
properties of natural rubber. Working in Woburn, MA in 1839, Goodyear
discovers that adding sulfur to natural rubber greatly enhances its elasticity
and toughness. His “sulfurized” rubber, later known as “vulcanized”
rubber, is still widely used today. While the Goodyear name is famous,
Charles Goodyear never realized fortune from his invention.
John Wesley Hyatt
John Wesley Hyatt, a printer and inventor from Albany NY, blended
nitrocellulose with camphor (sap from the laurel tree) to produce a
durable, colorful, and moldable thermoplastic known as celluloid (also
known as Pyroxylin) in 1868. Celluloid was the first commercially
successful semi-synthetic plastic. It was used for products such as
billiard balls, shirt collars, eyeglass frames and pen housings.
Dr. Leo H. Baekeland
The first synthetic plastic was discovered in 1907 when a Belgian born chemist, Dr. Leo H.
Baekeland, reacted phenol and formaldehyde under pressure using hexamethylenetetramine
as a catalyst for the reaction. The result was a thermosetting “phenolic” plastic he named
Bakelite. Compared to other plastics available at the time, such as celluloid, Baekeland’s
thermosetting phenolic was more stable. Once molded, this new material would not burn or
soften when reheated, or dissolve. This benefit made it stand out from the other plastics on
the market. Bakelite was an instant commercial success. It was electrically resistant,
chemically stable, heat resistant, rigid, moisture and weather resistant. It was very widely
used for its electrical insulating capability. Baekeland sold the rights to his invention to the
Eastman Kodak Company that first used it for camera bodies. It is also interesting to note
that J.W. Hyatt, inventor of celluloid and founder of the Hyatt-Burroughs Billiard Ball
Company, personally ordered his company to stop using celluloid and substitute Bakelite for
their billiard balls due to its superior performance.
Polyvinyl chloride (PVC) is one of the
most widely used thermoplastics in use
today, particularly in the building and
home construction industries where it is
used for siding, window profiles & pipe.
The commercialization of PVC in 1927 is the direct result of research work
that was conducted by Waldo Semon, a chemist working at the B.F.
Goodrich Rubber Company. While PVC was already known at the time, it
had no commercial value since it could not be processed without
degrading. Semon discovered that PVC could be melt processed without
degrading if a high boiling point liquid “plasticizer” was added to it. PVC
formulations can be either rigid or flexible depending their plasticizer
concentration. The very first applications for PVC included electrical wire
insulation.
1939: Wood TV Cabinet
Although polystyrene (PS) was unknowingly
discovered by a German apothecary in 1839, it was
not until 1930 that a scientist from the BASF
Corporation developed a commercial process for the
manufacture of PS. General purpose PS is a very
transparent but fairly brittle thermoplastic. Shortly
after its commercial introduction, other rubber
modified or rubber toughened grades, known as high
impact polystyrene (HIPS) were introduced.
PS and HIPS are still widely today for items that range from razor cartridges
to television cabinets. Television cabinets were initially wooden, then
thermoset phenolic, followed by flame retardant HIPS that is still used today.
1948: Phenolic TV Cabinet
1970: HIPS TV Cabinet
2003: HIPS TV Cabinet
The process of Injection Molding involves injecting hot (melted) plastic into a
closed mold cavity. Most early injection molding machines were imported from
Europe. The IM machine shown below was one of the first US built machines
and was manufactured by the HPM Corporation in Marion, OH. ( circa 1937)
General Motors introduced the Chevrolet Corvette in 1953. It was designed by
GM’s chief stylist Harley Earl, who was intrigued with the use of glass fiber
reinforced plastic as a body material. A total of 300 Corvettes were produced
in the first year of production, each containing forty one glass fiber reinforced
unsaturated polyester body parts. The 1953 Corvette was available only with a
white body and red interior, and sold for $3,498.00. While the Corvette has
changed dramatically over its 50 year history, one thing that has not changed
is the use of the glass fiber reinforced plastic body.
1953 Corvette
2003 50th Anniversary Corvette
On July 20, 1969 – the human race accomplished its greatest technological
achievement of all time when Neil Armstrong set foot on the moon. This
feat would not have been possible without many materials science
developments. Plastics played an important role. For example, the Apollo
A7L space suits were a multi-layer plastic structure comprised of nylon
fabric, neoprene coated nylon fabric, Dacron® (PET) fabric, aluminized
Mylar® (PET) film, Kapton® (PI) film, and Teflon® (PTFE) coated fabric.
The “fish bowl” helmet was produced from transparent polycarbonate.
The space suits of today make even more extensive use of plastics.
Plastics have been used for telephone housings since the turn of the
last century. The early black plastic phones were compression
molded from thermosetting phenolic and had wall thicknesses up to
13 mm. Injection molded ABS phones were introduced in the 1950’s.
ABS has a very high gloss, good impact resistance, and unlike
phenolic, could be molded in a variety of different colors. The ABS
phones had wall thicknesses of about 3 mm. Today’s cell phones are
injection molded using a polycarbonate & ABS blend (PC/ABS). The
compact and lightweight phones of today have wall thicknesses in the
range of 1 mm. Telephones are a good example of how plastic
products evolve over time. Creative product designers make use of
new plastic materials and new plastic processing technologies as they
become available in order to improve product performance.
Some of the most advanced plastic products being
manufactured today are used in the medical industry.
The angioplasty catheter is a good example of a life
saving medical device that would not be possible
without plastics. Balloon angioplasty is a minimally
invasive non-surgical alternative to coronary artery
bypass grafting surgery. The angioplasty balloon is
used to compress obstructing plaque in a clogged
artery against the arterial wall so that blood can flow
freely again. The doctor positions the balloon of the
angioplasty catheter at the site of the blockage and
gently expands it to compress the plaque and create a
wider opening in the artery. This procedure has a very
high success rate and greatly reduces the chances of
surgical complications.
Angioplasty balloons are
made from a variety of
plastics including PET,
nylon 11 or nylon 12.