Permanent Magnet Catalog

Permanent Magnet Catalog
Capabilities
Service
Exceptional customer service and an extensive on-the-shelf
inventory of all commercially available materials enable Dexter
Magnetic Technologies (DMT) to fulfill your permanent magnet requirements. With six locations in the United States, plus
an additional one in Europe, DMT responds to your needs
quickly and efficiently. In many cases orders are shipped the
same day they are received. DMT supplies permanent magnets
in virtually any quantity. Low quantity orders and credit card
purchases are welcome.
Engineering
Superior magnetic performance is a function of better magnetic
engineering. For customers who require design assistance or
complex circuit designs, a team of experienced application
engineers and knowledgeable field sales engineers is at your
service. Dextor Magnetic Technologies' dedicated R&D
professionals utilize the most advanced 3-D magnetic modeling
and validation tools to achieve better results in less time.
Customers are confident when they bring a complex concept or
new idea to DMT that we will meet that challenge by drawing
from our 50 years of proven magnetic expertise.
Fabrication
Experience and ability combined with cutting edge process
technology establishes DMT as the foremost magnet fabrication
expert. Sophisticated assembly techniques, ultra close tolerance
machining and automated production equipment enable DMT
to fulfill the most demanding requirements. Five fabrication
facilities, each with the full capacity to machine parts, allow
DMT to respond quickly to short lead times and large production
orders. Magnets weighing less than one gram to permanent
magnet assemblies weighing over one ton are accomplished
through DMT’s experience, ability and technologies.
Quality
The bottom line is measured in both quality and value. DMT
relies on rigorous quality assurance programs, which utilize
precise magnetic measurement, 3-D field mapping, calibration
and extensive testing. DMT’s QA programs comply with the
latest revisions of MIL-I-45208 and MIL-STD-45662. The results
aremagnets and assemblies that are delivered on time and
perform as designed, batch after batch, year after year.
Standard Products Table of Contents
■ Neodymium Iron Boron (NdFeB)
2
■ NeoForm™-B Bonded Neodymium Iron Boron (NdFeB)
6
■ Samarium Cobalt (SmCo)
10
■ Alnico
16
■ Ferrite (Ceramic & Flexible)
24
■ Magnetization Patterns
30
■ Standard Assemblies
31
■ Magnetic Design Calculations
36
This catalog includes the most often requested permanent
magnet shapes, sizes and magnetic materials. If you require a
shape, size or material not listed here, contact your nearest
Dexter Magnetic Technologies location at 1.800.566.4517.
No part of this catalog may be reproduced without prior written permission of Dexter Magnetic Technologies.
Copyright © 1998 - 2001, Dexter Magnetic Technologies
Disclaimer: THE INFORMATION SUPPLIED IN THIS DOCUMENT IS FOR GUIDANCE ONLY
AND SHOULD NOT BE CONSTRUED AS A WARRANTY. ALL IMPLIED WARRANTIES ARE
EXPRESSLY DISCLAIMED, INCLUDING WITHOUT LIMITATION ANY WARRANTY OF
MERCHANTABILITY AND FITNESS FOR USE.
All users of the material are responsible for assuring that its properties and specifications are suitable
for their needs, environment and the particular end use for which the material is purchased.
Users should consider the information contained in the Material Safety Data Sheet (MSDS) and product
label for the material in determining the appropriateness of the material for any particular application.
Users are responsible for determining, among other things, possible health hazards, appropriate
engineering controls and any precautions to be observed in using the material. Copies of the MSDS
and label are available upon request.
All data and specifications are subject to change as Dexter Magnetic Technologies deems appropriate.
®
PERMAG
Dexter Magnetic Technologies
MMPA Material Properties for NdFeB
Material
(BH)max (MGOe)
Br (Gauss)
Hc (Oersteds)
Hci (Oersteds)
■
NdFeB 31/25
31
11200
11000
25000
■
NdFeB 35/19
35
12300
11900
19000
■
NdFeB 38/17
38
12500
12100
17000
■
NdFeB 40/14
40
12600
12300
14000
■
NdFeb 44/12
44
13500
11000
12000
NdFeB Demagnetization Curves
14000
12000
10000
8000
6000
2000
-25000
-20000
-15000
-10000
*These properties and curves represent general grades of materials designated by the
Magnetic Materials Producers Association and serve as industry guidelines.
Do not design using these properties.
For actual (NdFeB) material properties, see page 5.
2
-5000
0
Magnetizing Force (Oersteds)
0
Flux Density (Gauss)
4000
NdFeB is the material of
choice for your high
performance applications. Part of the rare
earth family of magnetic
materials, NdFeB is the
highest energy material
currently available.
Energy products for
NdFeB magnets range
from 26 to 48 MGOe.
While NdFeB is less brittle
than some magnetic
materials, it should not
be used as a structural
component in your
application. NdFeB is
sensitive to heat and
should not be used in
environments that
exceed 150˚C (300˚F ).
Neodymium
Iron Boron
(NdFeB)
Dexter Magnetic Technologies
NdFeB Rounds
Part Number
Material
Diameter
Length
Orientation
PN35C1250B-N
N36
0.123
0.250
L
PN45C0140B
N45
0.140
0.500
D
PN45C0189B
N45
0.188
0.057
L
94C5668B
94EB
0.250
0.100
L
CM40685
4014
0.250
0.125
L
PN36C0250B
N36
0.250
0.250
L
97C5513B
97CB
0.250
2.000
L
97C5613B
97CB
0.251
0.200
L
PN45C1200B
N45
0.328
1.200
D
PN36SHC0330B
N36SH
0.330
0.330
L
94C5536C
94EB
0.370
0.250
L
97C5446C
97CB
0.375
0.125
L
94C5562B
94EB
0.375
2.100
L
94C4822B
94EA
0.499
0.188
L
NA67A460
34B
0.500
0.190
L
CM41085-2630
2630
0.500
0.250
L
CM41086-3220
3520
0.500
0.250
L
CM40713-3714
4014
0.500
0.250
L
CM41087-3714
4014
0.625
0.250
L
CM41088-2630
2630
0.625
0.250
L
CM40884-3714
4014
0.866
0.393
L
CM41089-3714
4014
0.875
0.500
L
CM41090-2630
2630
0.875
0.500
L
CM41091-2630
2630
1.000
0.500
L
CM41092-3220
3520
1.000
0.500
L
CM41093-3714
4014
1.000
0.500
L
D
L
NdFeB Rings
Part Number
Material
Outside
Diameter
Inside
Diameter
Length
PN36A1284B
N36
0.500
0.203
1.284
D
CM40672-3714
4014
0.660
0.135
0.557
L
PN37AA0600B
N37A
2.100
0.450
0.600
L
Orientation
OD
4
All dimensions listed in inches.
ID
L
Part Number
Material
Thickness
Width
Length
Orientation
CM41030-3714
4014
0.250
0.325
0.500
T
CM41094-2630
2630
0.250
0.500
0.500
T
CM41095-3220
3520
0.250
0.500
0.500
T
CM41096-3714
4014
0.250
0.500
0.500
T
PN36HR2933B
N36H
0.293
0.560
1.044
T
PN38HR0990B
N38H
0.315
0.750
0.990
T
PN38HR0375B
N38H
0.375
0.866
2.362
T
CM40325-3714
4014
0.500
0.750
0.750
T
CM40729-3714
4014
0.500
1.000
1.000
T
CM41097-2630
2630
0.500
1.000
1.000
T
CM41098-3220
3520
0.500
1.000
1.000
T
CM40975-3714
4014
0.590
0.750
0.750
T
PN38HR0122B
N38H
1.000
2.000
2.000
T
CM41099-2630
2630
1.000
2.000
2.000
T
CM40680-3714
4014
1.000
2.000
2.000
T
PN48R0100B
N48
1.000
2.000
2.000
T
L
Standard Parts Listing: NdFeB
NdFeB Blocks
T
W
Actual NdFeB Material Properties
Material
(BH)max (MGOe)
Br (Gauss)
Hc (Oersteds)
Hci (Oersteds)
2630
26
10500
10090
30000
3520
35
12000
11500
20000
34B
34
12000
11000
14000
4014
40
12900
12100
14000
94EA
28
10850
10350
17000
94EB
32
11600
11050
17000
97CB
36
12300
11800
16500
N36
37
12300
11500
13500
N36H
36
12200
10500
16000
N36SH
37
12200
11700
21000
N37A
35
12100
11600
14500
N38H
39
12700
11900
17000
N45
44
13550
10500
11500
N48
47
13750
10300
11000
Dexter Magnetic Technologies
■
1.800.566.4517
■
www.dextermag.com
5
Dexter Magnetic Technologies
NeoFormTM-B Bonded NdFeB Properties
Magnetic Characteristics
CGS
SI
Residual Induction Br
6900 G
0.69 T
Coercive Force Hc
5200 Oe
414 kA/m
Intrinsic Coercivity Hci
9000 Oe
716 kA/m
Energy Product (BH)max
10 MGOe
80 kJ/m3
1.22
1.22
Temperature Coefficient of Br to 100˚C
-0.105 %/˚C
-0.105 %/˚C
Temperature Coefficient of Hci to 100˚C
-0.40 %/˚C
-0.40 %/˚C
Required Magnetizing Force (Open Circuit) Hs
35000 Oe
2786 kA/m
150˚C
150˚C
6.0 g/cm3
6000 kg/m3
360˚C
360˚C
Recoil Permeability µr
Maximum Operating Temperature
Physical Properties
Density
Curie Temperature
* Maximum operating temperature depends
upon magnet geometry and operating
environment.
Coating - Operating environment and
application will drive the protective coating
requirements for NeoForm-B magnets.
Please speak to a Dexter engineer to review
coating alternatives, features and benefits.
NeoForm™-B Bonded NdFeB Demagnetization Curves
8000
7000
6000
5000
4000
3000
1000
-14000
■ -50˚C
6
-12000
■ 0˚C
-10000
■ 25˚C
■ 50˚C
-8000
■ 80˚C
-6000
■ 100˚C
■ 125˚C
-4000
■ 150˚C
-2000
0
Magnetizing Force (Oersteds)
*These properties and curves represent general grades of materials designed by the Magnetic Material Producers Association and serve as industry
guidelines. Do not design using these properties. For more information on this material, please contact us.
0
Flux Density (Gauss)
2000
NeoForm -B
Bonded
NdFeB
™
NeoForm combines the
high performance of
NdFeB with the diversity
of shapes and forms in
which bonded products
can be produced. Energy
products for NeoForm
magnets range from 8
to 10 MGOe. This
material is ideally suited
for intricate, ultra close
tolerance parts.
NeoForm is isotropic
and can be magnetized
in a variety of patterns.
NeoForm is best suited
for environments under
150˚C (300˚F ).
Dexter Magnetic Technologies
More applications for higher technology
Introducing NeoForm -B bonded
neodymium iron boron magnets from
Dexter Magnetic Technologies. NeoForm-B
combines many benefits of fully dense
NdFeB with the ability to manufacture
intricate shapes with exceptional precision.
The combination of material and process
used to manufacture these parts results
in a product with a number of tangible
benefits over other magnet materials.
Typical as pressed tolerances are .005"
and often times even better are possible.
In most cases NeoForm will not require
subsequent machining. Rapid prototyping
TM
combined with better than industry leadtimes will help speed new product designs
to market.
NeoForm magnets are isotropic,
enabling magnetization in virtually any
magnetic pattern. Plus, NeoForm magnets
are less brittle and stand up to handling
better than sintered magnets. Ideal for
use in the most advanced motors and
sensors, NeoForm magnets from Dexter
Magnetic Technologies can help drive
product quality and manufacturing
capacity to the levels required for higher
throughput and improved profitability.
NeoFormTM-B Bonded NdFeB Standard Parts
Blocks
Rings
Rounds
Thickness
Width
Length
0.125 - 0.750
0.500
0.500
Outside Diameter
Inside Diameter
Length
0.500
0.125
0.125 - 0.750
Diameter
Length
0.500
0.125 - 0.750
The above list represents the standard sizes that are currently available.
A wide range of unique shapes and sizes can be produced from NeoForm-B.
Call Dexter today for additional information.
8
Parts Listing: NeoForm Bonded NdFeB
Precision.
The NeoForm-B manufacturing
process, by eliminating the sintering
operation required for fully dense
magnets, maintains superior
mechanical tolerances. Due to the
elimination of the shrinkage associated with the sintering process,
NeoForm-B magnets seldom require
finish machining. This translates
into more cost-effective magnets.
Isotropic.
NeoForm-B magnets are isotropic.
Since they do not have a preferred
direction of magnetization, multiple
magnetization patterns including
axial, diametric, radial and
multi-pole are possible.
Dexter Magnetic Technologies
■
1.800.566.4517
■
Form.
In most instances, NeoForm-B magnets
can be compacted to the net shape
required. Features, that in the
production of fully dense magnets
require secondary machining, can be
formed in the die. This eliminates
subsequent machining operations
and provides greater consistency.
www.dextermag.com
9
Dexter Magnetic Technologies
MMPA Material Properties for SmCo
Material
(BH)max (MGOe)
Br (Gauss)
Hc (Oersteds)
Hci (Oersteds)
■
SmCo 16/18 (1-5)
16
8300
7500
18000
■
SmCo 18/20 (1-5)
18
8700
8000
20000
■
SmCo 22/15 (1-5)
22
9500
9000
15000
■
SmCo 26/11 (2-17)
26
10500
9000
11000
■
SmCo 28/7 (2-17)
28
10900
6500
7000
SmCo Demagnetization Curves
12000
10000
8000
6000
2000
-20000
-15000
-10000
*These properties and curves represent general grades of materials designated by the
Magnetic Materials Producers Association and serve as industry guidelines.
Do not design using these properties.
For actual (SmCo) material properties, see page 15.
10
-5000
0
Magnetizing Force (Oersteds)
0
Flux Density (Gauss)
4000
SmCo is an excellent
material for applications
that require high
performance in a high
temperature working
environment. Part of the
rare earth family of
magnetic materials,
SmCo exhibits excellent
thermal characteristics
with several grades
designed specifically for
applications up to 300˚C
(570˚F). Energy products
for SmCo materials
range from 16 to 32
MGOe. SmCo is second
only to NdFeB in
magnetic performance.
Samarium
Cobalt
(SmCo)
Dexter Magnetic Technologies
12
Samarium Cobalt Rounds
Part Number
Material
Diameter
Length
Orientation
PR26HC0135B
R26H
0.070
0.135
L
PR26HC4670B
R26H
0.070
0.275
L
PR26HC4633B
R26H
0.070
0.375
L
PR28EC3280B
R28E
0.094
0.312
L
PR28EC0800B
R28E
0.100
0.080
L
90C1798B
90A
0.125
0.125
L
PR28EC0125B
R28E
0.125
0.125
L
PR28EC4558B
R28E
0.125
1.014
L
PR26HC4647B
R26H
0.190
0.057
L
PR26HSC0194B
R26HS
0.194
0.139
L
90C5691B
90B
0.250
0.050
L
PR28EC4642B
R28E
0.250
0.067
L
90C90A
90B
0.250
0.100
L
30808
S3/225
0.250
0.100
L
PR26HEC4503B
R26HE
0.250
0.125
L
90C5230B
90B
0.250
0.250
L
PR28EC4653B
R28E
0.250
0.250
L
PR28EC4104B
R28E
0.250
1.709
L
96C5534B
96B
0.314
0.128
L
99C5627B
H-30CH
0.315
0.260
L
All dimensions listed in inches.
D
L
Standard Parts Listing: Samarium Cobalt
Samarium Cobalt Rounds Continued
Part Number
Material
Diameter
Length
Orientation
90A
0.375
0.125
L
P150C0130B
S2/150
0.375
0.125
L
PR28EC0250B
R28E
0.375
0.250
L
PR24EAC4570B
R24EA
0.375
0.280
L
PR28EC4651B
R28E
0.375
0.375
L
90C1826B
90A
0.395
0.285
L
96C5515B
96A
0.495
0.500
L
90C91B
90A
0.500
0.190
L
PR24EAC4104B
R24EA
0.500
0.190
L
PR28EC6250B
R28E
0.525
0.300
L
PR28EC4508B
R28E
0.540
0.200
L
PR24EAC4483B
R24EA
0.550
0.375
L
90C92A
90A
0.750
0.285
L
90C5440B
90A
0.900
0.125
L
S2/150
0.900
0.125
L
96C2173B
96A
1.000
0.375
L
96C5449B
96A
1.150
0.250
L
90C1928A
30936
Samarium Cobalt Rings
Part Number
Material
Outside
Diameter
Inside
Diameter
Length
PRE26A0100B
RE26
0.118
0.071
0.100
L
PRE26A0158B
RE26
0.118
0.071
0.157
L
PR26HSA6750B
R26HS
0.550
0.177
0.450
D
PR24EAA0573B
R24EA
0.573
0.288
0.115
L
PR26HA4569B
R26H
0.610
0.162
0.460
D
90A5397B
90A
0.750
0.430
0.250
L
R24EA
0.900
0.406
0.375
L
PR24EAA6129B
Dexter Magnetic Technologies
■
Orientation
1.800.566.4517
■
OD
www.dextermag.com
ID
L
13
Dexter Magnetic Technologies
14
Samarium Cobalt Blocks
Part Number
Material
Thickness
Width
Length
Orientation
90A
0.040
0.078
0.078
T
S3/225
0.079
0.197
0.197
T
PR28ES4505B
R28E
0.100
0.150
0.150
T
90S30A
90A
0.100
0.250
0.250
T
90S454B
90A
0.125
0.500
0.500
T
90S405A
90A
0.125
1.000
1.000
T
PR28ES4419B
R28E
0.187
0.187
0.250
L
90S31A
90A
0.210
0.500
0.500
T
PR28ES4187B
R28E
0.210
0.500
0.500
T
90R4512B
90B
0.250
0.500
1.000
T
96R1968B
96A
0.300
1.970
2.070
T
90S32A
90A
0.320
0.750
0.750
T
80A0567-2
S3/225
0.375
0.625
0.750
T
80A0566-2
S3/225
0.375
0.752
1.052
T
90R5675B
90B
0.425
1.060
1.060
T
PR26HSR0175B
R26HS
0.500
0.880
1.750
T
PR24EAS4326A
R24EA
0.535
2.070
2.070
T
PR26HS4518B
R26H
0.575
1.961
1.984
L
90S545B
90B
0.575
2.040
2.150
L
PR26HSR4702A
R26HS
0.646
1.972
2.010
L
PR26HSR4614A
R26HS
0.649
1.850
3.012
T
PR32HR2579B
R32H
0.984
1.300
2.579
T
90S424B
80A0496-2
All dimensions listed in inches.
L
T
W
Material
BHmax (MGOe)
B r (Gauss)
Hc (Oersteds)
Hci (Oersteds)
90A (1-5)
16
8200
7500
15000
90B (1-5)
18
8700
8200
15000
96A (1-5)
20
9000
8300
15000
96B (1-5)
22
9400
8800
15000
R24EA (2-17)
22
9900
7500
9250
R26H (2-17)
27
10600
9250
11500
R26HE (2-17)
26
10400
9250
12250
R26HS (2-17)
27
10700
9800
18000
R28E (2-17)
25
10350
8000
9250
H-30CH (2-17)
28
10900
9000
9500
R32H (2-17)
31
11600
9500
14000
RE26 (2-17)
26
10150
7500
10500
S2/150 (1-5)
19
8900
8600
20000
S3/225 (2-17)
26
10400
9500
16000
Dexter Magnetic Technologies
■
1.800.566.4517
■
www.dextermag.com
Standard Parts Listing: Samarium Cobalt
Actual Samarium Cobalt Material Properties
15
Dexter Magnetic Technologies
MMPA Material Properties for Alnico
Material
(BH)max (MGOe)
Br (Gauss)
Hc (Oersteds)
Hci (Oersteds)
■
Cast Alnico 5
5.5
12800
640
640
■
Cast Alnico 5-7
7.5
13500
740
740
■
Cast Alnico 8
5.3
8200
1650
1860
■
Sintered Alnico 2
1.5
7100
550
570
■
Sintered Alnico 5
3.9
10900
620
630
■
Sintered Alnico 8
4.0
7400
1500
1690
Alnico Demagnetization Curves
14000
12000
10000
8000
6000
2000
0
-2000
-1800
-1600
-1400
-1200
-1000
-800
-600
-400
-200
0
Magnetizing Force (Oersteds)
*These properties and curves represent general grades of materials designed by the Magnetic Material Producers Association and serve as industry
guidelines. Do not design using these properties. For more information on this material, please contact us.
16
Flux Density (Gauss)
4000
Alnico magnets are the
material of choice for
very high temperature
applications. They can
be used in environments
up to 550˚C (1020 ˚F)
and also in applications
where stability is needed
over wide temperature
ranges. Alnico is susceptible to stray magnetic
fields, which can lead to
demagnetization,
therefore, such environments should be avoided.
Energy products for
Alnico materials range
from 1.5 to 7.5 MGOe.
Alnico
Dexter Magnetic Technologies
Alnico Rounds
Part Number
Material
Diameter
Length
Orientation
20676
Sintered 2
0.120
0.250
*
25C2348A
Sintered 5
0.140
0.140
L
25C2331B
Sintered 5
0.311
0.500
L
29971
Sintered 8
0.106
0.160
L
28C87A
Sintered 8
0.120
0.187
L
S8A611
Sintered 8
0.125
0.125
L
S8A612
Sintered 8
0.125
0.250
L
28608
Sintered 8
0.125
0.370
L
28C2278A
Sintered 8
0.180
0.400
L
58065348
Sintered 8
0.188
0.450
L
28006
Sintered 8
0.215
0.187
L
S8A620
Sintered 8
0.250
0.062
L
S8A621
Sintered 8
0.250
0.125
L
28C2318A
Sintered 8
0.250
0.250
L
29770
Sintered 8
0.250
0.375
L
28C2302A
Sintered 8
0.260
0.795
L
28C2378B
Sintered 8
0.300
0.117
L
28C2372B
Sintered 8
0.305
0.155
L
S8A630
Sintered 8
0.375
0.125
L
S8A631
Sintered 8
0.375
0.250
L
28C2274B
Sintered 8
0.437
0.087
L
S8A640
Sintered 8
0.500
0.125
L
S8A641
Sintered 8
0.500
0.250
L
28C1926B
Sintered 8
0.625
0.250
L
* Material is unoriented and can be magnetized in any direction.
18
All dimensions listed in inches.
D
L
Part Number
Material
Diameter
Length
Orientation
P5C0032B
Cast 5
0.125
0.200
L
P5C4603B
Cast 5
0.125
0.562
L
P5C4680B
Cast 5
0.125
1.250
L
5A1
Cast 5
0.125
4.000
L
P5C4650B
Cast 5
0.185
1.000
L
P5C4599B
Cast 5
0.195
0.832
L
P5C4648B
Cast 5
0.202
2.750
L
P5C1250B
Cast 5
0.247
1.250
L
P5C0580B
Cast 5
0.250
0.580
L
P5C4671B
Cast 5
0.250
1.250
L
5C772A
Cast 5
0.375
1.250
L
5C1051B
Cast 5
0.375
2.000
L
P5C2105B
Cast 5
0.387
0.430
L
P5C2040B
Cast 5
0.500
2.040
L
P5C4005B
Cast 5
0.500
2.812
L
10055
Cast 5
0.500
3.000
L
5D64
Cast 5
0.689
0.430
L
P251
Cast 5
0.759
0.522
L
Cast 5-7
0.535
0.790
L
18551
Cast 8
0.125
4.000
L
21690
Cast 8
0.160
4.000
L
27546
Cast 8
0.250
0.500
L
27541
Cast 8
0.250
4.000
L
28320
Cast 8
0.378
0.905
L
MA14998
Cast 8
0.500
1.062
L
CD841
Cast 8
0.510
0.250
L
29293
Cast 8
0.760
0.250
L
29783
Cast 8
1.000
0.375
L
17C2334B
Dexter Magnetic Technologies
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Standard Parts Listing: Alnico
Alnico Rounds continued
19
Dexter Magnetic Technologies
Alnico Rings
Part Number
Material
Outside
Diameter
Inside
Diameter
Length
Orientation
22A3A
Sintered 2
0.250
0.080
0.062
*
22A25B
Sintered 2
0.270
0.110
0.400
*
22A29A
Sintered 2
0.375
0.093
0.125
*
28A3004A
Sintered 8
0.250
0.080
0.134
D
30658
Sintered 8
0.260
0.098
0.330
L
29302
Sintered 8
0.275
0.110
0.300
L
29833
Sintered 8
0.375
0.093
0.125
D
S8F576
Sintered 8
0.415
0.210
0.125
L
28A4B
Sintered 8
0.500
0.187
0.187
D
S8F577
Sintered 8
0.525
0.250
0.150
L
29266
Sintered 8
0.644
0.387
0.115
L
SG8722
Sintered 8
0.750
0.116
0.125
L
28A3008A
Sintered 8
0.785
0.133
0.140
D
30230
Cast 5
0.852
0.477
0.570
D
5F117
Cast 5
1.000
0.500
0.125
L
5G130
Cast 5
1.000
0.750
0.500
L
30229-2
Cast 5
1.165
0.610
0.375
D
8F506
Cast 8
0.520
0.250
0.140
L
30552
Cast 8
0.690
0.170
0.580
L
8F508
Cast 8
0.910
0.475
0.270
L
22392
Cast 8
1.250
0.420
2.100
L
17644
Cast 8
1.500
0.750
0.340
L
8F511
Cast 8
1.940
0.950
0.270
L
* Material is unoriented and can be magnetized in any direction.
20
All dimensions listed in inches.
OD
ID
L
Part Number
Material
Thickness
Width
Length
Orientation
22S4A
Sintered 2
0.062
0.062
0.375
*
22S2A
Sintered 2
0.062
0.062
0.750
*
22S1A
Sintered 2
0.125
0.125
0.760
*
22R26A
Sintered 2
0.187
0.260
0.885
*
S5B558
Sintered 5
0.062
0.062
0.500
L
25R22A
Sintered 5
0.062
0.125
0.500
L
25S286A
Sintered 5
0.125
0.125
0.750
L
25065260
Sintered 5
0.125
0.250
0.808
L
25R2126A
Sintered 5
0.275
0.350
0.855
L
30018
Sintered 8
0.125
0.125
0.375
L
28R24A
Sintered 8
0.125
0.250
0.500
L
29966
Sintered 8
0.130
0.180
0.385
T
28R2127A
Sintered 8
0.290
0.370
0.455
L
5B24
Cast 5
0.125
0.375
4.000
L
9744
Cast 5
0.125
0.500
2.500
W
27745
Cast 5
0.140
0.265
3.000
W
30327
Cast 5
0.175
0.500
2.000
W
P5C0975B
Cast 5
0.187
0.187
0.975
L
5R2135A
Cast 5
0.232
0.661
1.448
W
5R2074B
Cast 5
0.411
0.528
0.667
L
MA15696
Cast 5
0.485
0.735
0.790
L
17R2124B
Cast 5-7
0.340
0.670
3.000
L
B707
Cast 5-7
0.500
0.500
3.000
L
29273
Cast 8
0.117
0.300
4.250
T
29272
Cast 8
0.117
0.410
4.000
T
30825
Cast 8
0.165
0.251
4.000
W
21390
Cast 8
0.187
0.250
4.000
L
8B472
Cast 8
0.250
0.250
4.000
L
8R694A
Cast 8
0.274
0.497
2.125
T
MA16314
Cast 8
0.450
1.075
3.350
L
8B476
Cast 8
0.625
0.625
4.000
L
27835
Cast 8
1.000
1.000
4.000
L
Dexter Magnetic Technologies
■
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■
L
Standard Parts Listing: Alnico
Alnico Blocks
T
W
www.dextermag.com
21
Dexter Magnetic Technologies
Alnico Horseshoes
Part Number
Material
A
B
C
D
E
5K207
Cast 5
1.250
0.750
1.218
0.250
0.375
5U41B
Cast 5
1.330
1.090
1.195
0.431
0.317
U177
Cast 5
1.625
1.625
0.844
1.125
0.813
A
C
E
B
D
Alnico Round Horseshoes
22
Part Number
Material
A
B
C
D
E
F
22U73A
Sintered 2
0.312
0.190
0.141
0.095
0.050
0.080
22U74A
Sintered 2
0.365
0.210
0.170
0.100
0.096
0.120
SU1607
Sintered 2
0.400
0.187
0.172
0.130
0.078
0.098
22U5A
Sintered 2
0.400
0.202
0.125
0.094
0.093
–
22U75A
Sintered 2
0.400
0.202
0.172
0.130
0.093
0.099
22U76B
Sintered 2
0.455
0.187
0.200
0.160
0.085
0.095
22U77A
Sintered 2
0.500
0.250
0.270
0.125
0.125
0.141
22U13B
Sintered 2
0.510
0.272
0.187
0.187
0.115
0.100
22U14A
Sintered 2
0.510
0.457
0.187
0.187
0.125
0.100
U181
Cast 5
0.437
0.437
0.260
0.160
0.220
0.140
5H153
Cast 5
0.687
0.688
0.344
0.344
0.344
0.187
5H148
Cast 5
0.750
0.500
0.375
0.375
0.250
0.218
5H154
Cast 5
0.875
0.875
0.406
0.406
0.438
0.250
5H149
Cast 5
0.875
1.000
0.375
0.375
0.500
0.250
U185
Cast 5
1.000
1.000
0.406
0.354
0.500
0.265
5H151
Cast 5
1.500
1.750
0.625
0.625
0.875
0.375
All dimensions listed in inches.
A
C
D
E
B
F
Standard Parts Listing: Alnico
Alnico Rectangular Horseshoes
Part Number
Material
A
B
C
D
E
F
55A782
Sintered 2
0.375
0.172
0.312
0.068
0.205
0.125
22U15B
Sintered 2
0.375
0.325
0.312
0.142
0.250
0.130
22U79B
Sintered 2
0.400
0.187
0.250
0.072
0.180
0.090
22U18B
Sintered 2
0.735
0.281
0.365
0.093
0.260
0.135
22U17A
Sintered 2
0.875
0.391
0.375
0.188
0.250
0.120
MA16006
Cast 5
0.580
0.375
0.720
0.200
0.200
–
5K245
Cast 5
1.500
0.875
0.500
0.312
0.500
–
C
A
E
D
B
F
Alnico Rotors
Material
Type
Outside
Diameter
Inside
Diameter
Length
# Poles
5H166
Cast 5
A
1.000
0.250
0.750
4
5E95
Cast 5
B
1.156
0.360
0.330
6
5H177
Cast 5
A
1.250
0.250
0.750
6
CT903
Cast 5
A
1.250
0.265
0.750
6
5X12B
Cast 5
A
1.278
0.450
0.750
6
5H178
Cast 5
A
1.500
0.375
0.875
6
5X13B
Cast 5
A
2.000
0.500
1.250
8
A281
Cast 6
A
2.875
1.437
1.266
6
Part Number
Type A
S
ID
N
S
N
S
OD
N
L
Type B
ID
OD
L
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23
Dexter Magnetic Technologies
MMPA Material Properties for Ferrite
Material
(BH)max (MGOe)
Br (Gauss)
Hc (Oersteds)
Hci (Oersteds)
■
Ceramic 1
1.05
2300
1860
3250
■
Ceramic 5
3.40
3800
2400
2500
■
Ceramic 8
3.50
3850
2950
3050
Ceramic Ferrite Demagnetization Curves
4500
4000
3500
3000
2500
2000
1500
500
-3500
-3000
-2500
-2000
-1500
-1000
-500
0
Magnetizing Force (Oersteds)
*These properties and curves represent general grades of materials designed by the Magnetic Material Producers Association and serve as industry
guidelines. Do not design using these properties. For more information on this material, please contact us.
24
0
Flux Density (Gauss)
1000
Ferrite is the best selling
Ferrite
magnetic material in
the world because of the
low cost and abundance
of the raw materials
used in its manufacture.
This material is best
suited for environments
under 300˚C (570˚F).
The hard crystalline
structure of this material
makes it brittle, therefore
small cracks and chips
on these magnets are
to be expected. Such
imperfections do not
interfere with the
performance of the
magnets. Energy
products for ferrite
materials range from
1 to 3.5 MGOe.
(Ceramic &
Flexible)
Dexter Magnetic Technologies
Ceramic Ferrite Rounds
Part Number
Material
Diameter
Length
Orientation
P61C0125B
1
0.250
0.125
*
P61C0187B
1
0.500
0.187
*
P61C0274B
1
0.500
0.274
*
70012-1
1
0.625
0.130
*
P68C0200B
8
0.261
0.200
L
P65C0281B
5
0.268
0.281
L
P68C0187B
8
0.324
0.187
L
P65C0205B
5
0.375
0.205
L
P68C0750B
8
0.490
0.750
L
646200
8
0.495
0.250
L
P68C0125B
8
0.500
0.125
L
P68C0001B
8
0.500
0.500
L
P68C0514B
8
0.515
0.500
L
P68C0620B
8
0.620
0.620
L
P68C0625B
5
0.625
0.350
L
P68C0183B
8
0.680
0.183
L
P68C0002B
8
0.750
0.250
L
P68C0875B
8
0.875
1.000
L
P68C0500B
8
1.180
0.524
L
P68C0250B
8
1.250
0.250
L
P68C0325B
8
1.500
0.325
L
* Material is unoriented and can be magnetized in any direction.
26
All dimensions listed in inches.
D
L
Material
Outside
Diameter
Inside
Diameter
Length
P61A0485B
1
0.455
0.155
0.485
*
86147
1
0.479
0.280
0.125
*
60098-2U
1
0.500
0.187
0.125
*
CM-365-.110
1
0.600
0.410
0.110
*
321A-.200
1
0.625
0.255
0.200
*
120B
1
0.750
0.271
0.250
*
CM387-.079
1
0.750
0.533
0.079
*
60109
1
0.751
0.500
0.125
*
CM-829
1
0.846
0.530
0.079
*
60081
1
1.079
0.218
0.125
*
P61AO25OB
1
1.079
0.597
0.250
*
P61AO255B
1
1.125
0.375
0.250
*
CM-0249
1
1.493
0.505
0.375
*
P61A0375B
1
1.623
0.705
0.375
*
60124
1
2.025
1.325
1.000
*
646330
8
1.500
0.500
0.187
L
P65A0275B
5
1.771
0.866
0.275
L
65A2902B
5
1.772
0.866
0.197
L
26225
8
1.789
0.800
0.195
L
29784
8
1.900
1.201
0.137
L
65A0053B
5
2.100
0.800
0.275
L
65A50128
5
2.380
1.000
0.280
L
65A60133
5
2.800
1.203
0.330
L
65A60140
5
2.800
1.203
0.400
L
65A60266
5
2.800
1.203
0.660
L
MF51112
5
3.200
1.600
0.500
L
65A90143
5
3.376
1.280
0.425
L
65A90385
5
3.376
1.280
0.850
L
P65A0400B
5
4.540
1.750
0.400
L
65A2502B
5
5.050
2.312
0.650
L
65A8039B
5
5.250
2.312
0.550
L
65A8003B
5
6.125
2.800
0.825
L
65A2483BL
5
7.500
3.250
0.745
L
Part Number
Dexter Magnetic Technologies
■
Orientation
1.800.566.4517
■
OD
www.dextermag.com
ID
L
Standard Parts Listing: Ferrite (Ceramic)
Ceramic Ferrite Rings
27
Dexter Magnetic Technologies
Ceramic Ferrite Blocks
Part Number
Material
Thickness
Width
Length
Orientation
CM-309
1
0.062
0.125
0.250
*
40587
1
0.125
0.125
0.940
*
147A
1
0.177
0.750
1.000
*
40057-1
1
0.187
0.187
1.062
*
CM-0410
1
0.195
0.205
0.424
*
P61R0500B
1
0.250
0.250
0.500
*
469-.125
1
0.625
0.390
0.125
*
P68R0550B
8
0.100
0.550
0.550
T
P68R4582B
8
0.125
0.200
0.313
T
P68R1002B
8
0.145
0.187
0.622
T
P65R1990B
5
0.170
0.750
1.990
T
P68R1150B
8
0.187
0.210
1.150
T
P68R0197B
8
0.197
0.750
1.975
T
P68R0004B
8
0.375
0.470
0.595
T
P68R0005B
8
0.375
0.485
0.860
T
P68R1875B
8
0.375
0.875
1.879
T
P68R0006B
8
0.375
1.985
2.235
T
P4488
8
0.387
0.866
1.878
T
P65R0875B
5
0.392
0.875
1.875
T
P65R0100B
5
0.400
0.625
1.000
T
MF51105
8
0.500
3.585
10.625
T
68R8611B
8
1.000
4.000
6.000
T
* Material is unoriented and can be magnetized in any direction.
28
All dimensions listed in inches.
L
T
W
Thickness
Width
Length
0.035
0.250 - 6.000
100 ft rolls
0.060
0.250 - 6.000
100 ft rolls
Thickness
Width
Length
0.020 - 0.090
0.250 - 6.000
100 ft rolls
0.125
0.375 - 6.000
50 ft rolls
0.156 - 0.375
0.375 - 6.000
36 inches
With Adhesive
Without Adhesive
Flexible Ferrite Sheet Holding Force
Typical holding force without steel backup
35
35
30
30
25
25
Holding force in oz/in2
Holding force in oz/in2
Typical holding force with 0.010''steel backup
20
A
15
10
B
20
15
A
10
B
5
0
Standard Parts Listing: Ferrite (Flexible)
Flexible Ferrite Sheets and Strips
5
2
4
6
8
10
15
0
20
2
4
6
8
10
15
20
Air gap in 0.001''
Air gap in 0.001''
Steel used in magnetic circuit was SAE 1010 - 1020
A 11 ppi 0.055''
B 18 ppi 0.030''
A 11 ppi 0.055''
B 18 ppi 0.030''
Combining magnetic ferrite powders with a flexible rubber binder and rolling it
creates flexible magnetic sheets. The sheets come in many different thicknesses
and can be cut to varying widths. This material is flexible and holds to curved
surfaces. The sheets are magnetized with a multipole pattern to generate the
maximum holding force. The amount of holding force is proportional to the
surface area of the magnetic material.
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29
Dexter Magnetic Technologies
Magnetization Patterns &
Preferred Direction
Not all magnets or magnetic
materials can be magnetized in any
direction. Most magnets have a preferred
direction of magnetization which results
from the orientation of magnetic domains.
By exposing the magnet to an external
magnetic field during processing a
preferred direction is achieved.
Isotropic magnets are unoriented
and have no preferred direction; therefore
it is possible to magnetize them in any
direction. Alnico 2, Ceramic 1, and most
bonded NdFeB are isotropic materials.
Almost all other materials are anisotropic
and have a preferred direction of
magnetization. They will exhibit the best
magnetic properties when magnetized
in that direction. Higher magnetic flux
densities can be achieved with anisotropic
magnets that are magnetized in their
direction of orientation than with
isotropic magnets.
N
N
S
S
Parallel to Width
Parallel to Diameter
S
N
S
N
Parallel to Length
Parallel to Length
S
N
N
S
Parallel to Thickness
Parallel to Thickness
N
S
N
2 Poles / 1 Face
N S
N S
N S
Multiple Poles on 1 Face
30
S
Parallel to Diameter
N
S
S
N
4 Poles on Outside Diameter
While magnets can
perform many useful
functions independently,
in most cases their usefulness is improved by
combining them with
soft steel pole pieces to
create what is called a
“magnetic assembly”.
The use of magnetic
assemblies dates back to
the 1600’s, when William
Gilbert added soft iron
caps to enhance and
concentrate the flux
from lodestones. Since
then, the combination
of magnets and steel
has enabled many
technologies by shaping
and directing the fields
created by a magnet.
Standard
Assemblies
Dexter Magnetic Technologies
2 Pole Ceramic Cup Assemblies
Part #
Diameter
Length
Pull lbs.
PMC-375
0.375
0.500
1.8
PMC-379
0.375
1.000
2.4
PMC-500
0.500
0.500
2.6
PMC-625
0.625
0.500
3.8
PMC-626
0.625
0.625
6.5
PMC-629
0.625
1.000
7.5
PMC-750
0.750
0.500
4.0
PMC-879
0.875
1.000
14.4
D
L
A flat ceramic magnet, sandwiched between steel pole pieces, is potted with
epoxy in a non-ferrous shell.
Alnico 5 Sheathed Holding Assemblies
Part #
Diameter
Length
Pull lbs.
Pull 2 Poles
PMS-1250
0.125
0.250
0.06
–
PMS-1252
0.125
0.500
0.25
–
PMS-1870
0.187
0.250
0.12
–
PMS-1872
0.187
0.500
0.25
–
PMS-2500
0.250
0.250
0.13
0.35
PMS-2501
0.250
0.375
0.25
0.37
PMS-2502
0.250
0.500
0.40
0.40
PMS-2504
0.250
0.750
0.81
–
PMS-2506
0.250
1.000
1.19
–
PMS-3120
0.312
0.250
0.18
0.81
PMS-3121
0.312
0.375
0.31
0.81
PMS-3750
0.375
0.250
0.18
1.00
PMS-3751
0.375
0.375
0.37
1.20
PMS-5000
0.500
0.500
0.50
2.70
A cast Alnico 5 magnet, magnetized along its length or with 2 poles on one face,
is tightly encased in a non-magnetic stainless steel tube and supplied ready for
insertion. The stainless sheath prevents undue loss of magnetic flux at the magnet
pole when inserted directly into steel components.
32
All dimensions listed in inches.
D
L
Part #
Diameter
Length
Pull lbs.
Thread Size
PMO86-2
0.250
0.625
0.30
6-32
PMO88-1
0.375
0.500
1.43
6-32
PMO89-1
0.437
0.500
1.95
6-32
PMO90-1
0.500
0.500
2.50
6-32
PMO90-2
0.500
0.625
3.00
6-32
PMO91-1
0.625
0.500
2.40
10-24
PMO91-3
0.625
0.750
4.10
10-24
PMO91-9
0.625
1.500
8.00
10-24
PMO92-2
0.750
0.625
7.40
10-24
PMO92-3
0.750
0.750
9.10
10-24
PMO93-2
0.875
0.625
12.40
10-24
PMO94-1
1.000
0.500
7.40
1/4-20
PMO94-3
1.000
0.750
14.00
1/4-20
PMO94-5
1.000
1.000
16.00
1/4-20
PMO94-7
1.000
1.250
17.50
1/4-20
PMO95-5
1.250
1.000
22.00
1/4-20
PMO95-7
1.250
1.250
25.00
1/4-20
PMO95-8
1.250
1.400
36.00
1/4-20
D
Standard Parts Listing: Assemblies
Alnico 5 Cup Holding Assemblies
L
Thread
A center pole of cast Alnico 5 is insulated with a non-magnetic spacer inside a
soft iron cup with a threaded mounting hole.
X-Cups (Low Profile Base Assembly)
Part #
A
B
C
D
Pull lbs.
X20
1.200
0.210
0.180
0.125
5
X50
2.030
0.800
0.270
0.190
30
X70
2.800
1.000
0.375
0.250
70
X80
3.200
1.203
0.435
0.400
90
X150
4.900
2.190
0.435
0.500
150
Permanent magnet bonded in a round plated cup. Durable, can not be
demagnetized, high slide resistance and easy mounting. Adapters for
mounting supplied upon request.
Dexter Magnetic Technologies
■
1.800.566.4517
■
A
B
C
D
www.dextermag.com
33
Dexter Magnetic Technologies
Magnetic Holding Assemblies
Part #
A
B
C
Pull lbs.
PMA-01
3.000
1.000
1.187
40
A compact permanent magnet assembly made from Alnico. Supplied with a
1/4 - 20 thread mounting hole.
B
A
C
Part #
ZZ14
A
B
C
Pull lbs.
1.000
1.250
0.375
10
A ceramic permanent magnet held together with a brass eyelet through the center
of the assembly. Holding force on the ends of pole pieces.
C
B
A
Ceramic Wall Holders
Part #
Thickness
Width
Length
S208 (Blue)
0.625
1.125
1.187
S208A (Red)
0.625
1.125
1.187
S208B (Beige)
0.625
1.125
1.187
S208D (White)
0.625
1.125
1.187
S216 (Blue)
0.625
1.125
2.125
S216A (Red)
0.625
1.125
2.125
S216BR (Brown)
0.625
1.125
2.125
S216D (White)
0.625
1.125
2.125
S216F (Green)
0.625
1.125
2.125
A ceramic holding assembly enclosed in colored plastic.
34
All dimensions listed in inches.
W
T
L
Standard Parts Listing: Assemblies
Magnetic Hanger or Ring Assemblies
Part #
A
B
C
Pull lbs.
DV77
3.200
1.203
0.435
90
DV78
3.200
1.203
0.435
90
A ceramic holding assembly with either a hanger bar or eye bolt attached.
A
B
C
A
B
C
Magnetic Picture Hanger
Part #
Thickness
Width
Length
Holding Force
PK101
0.100
3.000
2.000
2
PK102
0.100
4.000
2.000
5
PK103
0.100
4.000
4.000
12
PK104
0.100
8.000
4.000
20
L
The magnetic picture hanger is a metal plate with a hook on one side and a
magnetic strip on the other.
T
W
Dexter Magnetic Technologies
■
1.800.566.4517
■
www.dextermag.com
35
Dexter Magnetic Technologies
Magnetic Design Calculations
How to Determine Magnet Length
where lm = required length (cm) of magnet
Bg = flux density (Gauss) desired in the air gap (equal numerically to Hg, in air)
lg = length (cm) of the air gap parallel to lines of flux
Hd = magnetizing force (Oersteds) of the magnet, corresponding to an
assumed operating point on the demagnetization curve.
How to Determine Magnet Area
where Am = necessary area (square cm) of magnet perpendicular to direction of
magnetization
Bg = flux density (Gauss) desired in the air gap (equal numerically to Hg, in air)
Ag = Cross sectional area (square cm) of the air gap perpendicular to lines of flux
Bd = flux density (Gauss) of the magnet, corresponding to the operating point
of the demagnetization curve.
How to Determine Load Line
Once the size and shape of the magnet are established, its load line, B/H,
can be found as follows:
Combining the two equations:
lm =
Bglg
Hd
Am =
BgAg
Bd
Am =
BgAg
BgAg
therefore, Bd =
Bd
Am
lm =
Bglg
Hd
therefore, Hd =
combining the two equations:
BgAg
Aglm
Am
Bd
=
=
Amlg
Bglg
Hd
lm
How to Determine Flux Density
Draw a line having a slope of Bd/Hd through the origin and the second
quadrant. Read the value of Bd where this line intersects the demagnetization
curve to get the actual operating point for the magnet. Substitute this value in
the following formula:
Substitute the new operating point data (Bd, Hd ) into the above Length and
Area calculations and recalculate until the desired Bg is achieved.
36
Bglg
lm
Bg =
AmBd
Ag
Dexter Magnetic Technologies publishes
additional information on a variety of
subjects including:
■
■
■
■
■
Magnetic Technology
Design Calculations
Neoform-B Bonded NdFeB Magnets
Application Notes
Dexter Magnetic Technologies’
Design, Fabrication and
Assembly Capabilities
Call 1.800.566.4517 to request
the above literature or any additional
information regarding permanent magnets.
In addition, Dexter Magnetic Technologies
is the leading distributor of ferrite cores and
accessories, thermistors and EMC components.
For information regarding these products call
1.800.775.3829.
Contact Information
Boston Area
229 Billerica Road
Chelmsford, MA 01824-4167
(510) 656-9502 tel
(510) 809-4533 fax
United Kingdom
80 Heron Drive
Langley, Slough
Berkshire, SL38XP England
44-1753-73-74-00 tel
44-1753-73-74-01 fax
Chicago Area
1050 Morse Avenue
Elk Grove Village, IL 60007-5110
(847) 956-1140 tel
(847) 956-8205 fax
Los Angeles Area
18000 Studebaker Road, Suite 350
Cerritos, CA 90703-2690
(562) 809-3363 tel
(562) 809-4533 fax
New York Area
400 Karin Lane
Hicksville, NY 11801-5352
(516) 822-3311 tel
(516) 822-3315 fax
Silicon Valley
48460 Kato Road
Fremont, CA 94538-7337
(510) 656-5700 tel
(510) 668-5422 fax
Toledo/Detroit Area
4303 Talmadge Road
Toledo, OH 43623
(419) 475-6298 tel
(419) 475-6987 fax
In the continental United States call toll free
1.800.566.4517
or contact us on the world wide web @
www.dextermag.com