Alliance LLC Fundamentals of Permanent Magnets. Magnetic Orientation Isotropic Anisotropic...
-
Upload
donna-hicks -
Category
Documents
-
view
232 -
download
2
Transcript of Alliance LLC Fundamentals of Permanent Magnets. Magnetic Orientation Isotropic Anisotropic...
![Page 1: Alliance LLC Fundamentals of Permanent Magnets. Magnetic Orientation Isotropic Anisotropic (non-oriented) (oriented) Magnetic strength is the same.](https://reader033.fdocuments.us/reader033/viewer/2022050721/56649d955503460f94a7e5ca/html5/thumbnails/1.jpg)
Alliance LLC
Fundamentals of Permanent Magnets
![Page 2: Alliance LLC Fundamentals of Permanent Magnets. Magnetic Orientation Isotropic Anisotropic (non-oriented) (oriented) Magnetic strength is the same.](https://reader033.fdocuments.us/reader033/viewer/2022050721/56649d955503460f94a7e5ca/html5/thumbnails/2.jpg)
Magnetic Orientation
Isotropic Anisotropic (non-oriented) (oriented)
•Magnetic strength is the same in all directions
•Can be magnetized in any direction
•Almost all bonded magnets
•Magnetic strength is greatest in the oriented direction
•Can be magnetized only in the oriented direction
•Almost all sintered magnetsProperty of Alliance LLC
![Page 3: Alliance LLC Fundamentals of Permanent Magnets. Magnetic Orientation Isotropic Anisotropic (non-oriented) (oriented) Magnetic strength is the same.](https://reader033.fdocuments.us/reader033/viewer/2022050721/56649d955503460f94a7e5ca/html5/thumbnails/3.jpg)
Main Magnetic Properties
Residual induction - Br
Coercive force - Hc
Intrinsic coercive force - Hci
Maximum Energy Density – (BH)max
Maximum Working Temperature - Tw Reversible Temperature Coefficient - -%Br/C Curie Temperature - Tc
Property of Alliance LLC
![Page 4: Alliance LLC Fundamentals of Permanent Magnets. Magnetic Orientation Isotropic Anisotropic (non-oriented) (oriented) Magnetic strength is the same.](https://reader033.fdocuments.us/reader033/viewer/2022050721/56649d955503460f94a7e5ca/html5/thumbnails/4.jpg)
Main Types of Magnet Materials
Alnico Ferrite Samarium Cobalt Neodymium Iron Boron Bonded Grades of the Above Types
Property of Alliance LLC
![Page 5: Alliance LLC Fundamentals of Permanent Magnets. Magnetic Orientation Isotropic Anisotropic (non-oriented) (oriented) Magnetic strength is the same.](https://reader033.fdocuments.us/reader033/viewer/2022050721/56649d955503460f94a7e5ca/html5/thumbnails/5.jpg)
Typical Supplier Data Sheet
Property of Alliance LLC
![Page 6: Alliance LLC Fundamentals of Permanent Magnets. Magnetic Orientation Isotropic Anisotropic (non-oriented) (oriented) Magnetic strength is the same.](https://reader033.fdocuments.us/reader033/viewer/2022050721/56649d955503460f94a7e5ca/html5/thumbnails/6.jpg)
Hysteresis / Demagnetization Curve
Property of Alliance LLC
![Page 7: Alliance LLC Fundamentals of Permanent Magnets. Magnetic Orientation Isotropic Anisotropic (non-oriented) (oriented) Magnetic strength is the same.](https://reader033.fdocuments.us/reader033/viewer/2022050721/56649d955503460f94a7e5ca/html5/thumbnails/7.jpg)
I
I
Hci
Br, Bi
Hc-H
-B
+H
+B
(BiH)max
Property of Alliance LLC
![Page 8: Alliance LLC Fundamentals of Permanent Magnets. Magnetic Orientation Isotropic Anisotropic (non-oriented) (oriented) Magnetic strength is the same.](https://reader033.fdocuments.us/reader033/viewer/2022050721/56649d955503460f94a7e5ca/html5/thumbnails/8.jpg)
Temperature Effects
Property of Alliance LLC
![Page 9: Alliance LLC Fundamentals of Permanent Magnets. Magnetic Orientation Isotropic Anisotropic (non-oriented) (oriented) Magnetic strength is the same.](https://reader033.fdocuments.us/reader033/viewer/2022050721/56649d955503460f94a7e5ca/html5/thumbnails/9.jpg)
25.0 22.5 20.0 17.5 15.0 12.5 10.0 7.50 5.00 2.50 H (KOe)
15.0
13.5
12.0
10.5
9.00
7.50
6.00
4.50
3.00
1.50
B (Kg)
Alnico Ferrite SmCo NdFeB(SH)
Surface Flux at 0" Gap of 1" dia. Disc
0
1000
2000
3000
4000
5000
6000
0.25 0.5 1 2 4 8
Length of Magnet in inches
Ga
us
s
Property of Alliance LLC
![Page 10: Alliance LLC Fundamentals of Permanent Magnets. Magnetic Orientation Isotropic Anisotropic (non-oriented) (oriented) Magnetic strength is the same.](https://reader033.fdocuments.us/reader033/viewer/2022050721/56649d955503460f94a7e5ca/html5/thumbnails/10.jpg)
Magnet CharacteristicsMaterials Typical Shapes Pro Con
Cast AlnicoAlNiCo
Rods, Bars, U shapeand other cast type
High BrHigh working TGood T coef.
Very Low HcHigh costHigh L/D
Requires Cast
Sintered AlnicoAlNiCo
Powder pressed to shapeComplex shapes
High Br, T
Requires Tool High cost Low market
Ceramic/FerriteSrFe2O3
Blocks, Rings, Arcs, DiscsMost flux for $
High usageLow corrosion
Low BrRequires tool
Simple shapes
SamariumCobaltSmCo
Blocks, Rings, DiscsArcs, Segments
No corrosionVery low T coefStable, No tool
Very expensiveSimple shapes
High Co content
NeodymiumNdFeB
Blocks, Rings, DiscsArcs, Segments
Highest magnetic properties
No tooling
CorrodesLow working TDifficult to Mag
Bonded GradesAll materials
Difficult geometriesCan be insert molded
or over-molded
Complex shapesVarious resins
High toolingLow magneticsHigh volumes
Property of Alliance LLC
![Page 11: Alliance LLC Fundamentals of Permanent Magnets. Magnetic Orientation Isotropic Anisotropic (non-oriented) (oriented) Magnetic strength is the same.](https://reader033.fdocuments.us/reader033/viewer/2022050721/56649d955503460f94a7e5ca/html5/thumbnails/11.jpg)
Cast Alnico Magnets
Property of Alliance LLC
![Page 12: Alliance LLC Fundamentals of Permanent Magnets. Magnetic Orientation Isotropic Anisotropic (non-oriented) (oriented) Magnetic strength is the same.](https://reader033.fdocuments.us/reader033/viewer/2022050721/56649d955503460f94a7e5ca/html5/thumbnails/12.jpg)
Ferrites / Ceramics (SrFe2O3)
Property of Alliance LLC
![Page 13: Alliance LLC Fundamentals of Permanent Magnets. Magnetic Orientation Isotropic Anisotropic (non-oriented) (oriented) Magnetic strength is the same.](https://reader033.fdocuments.us/reader033/viewer/2022050721/56649d955503460f94a7e5ca/html5/thumbnails/13.jpg)
Neodymium, Neo, NdFeB
Property of Alliance LLC
![Page 14: Alliance LLC Fundamentals of Permanent Magnets. Magnetic Orientation Isotropic Anisotropic (non-oriented) (oriented) Magnetic strength is the same.](https://reader033.fdocuments.us/reader033/viewer/2022050721/56649d955503460f94a7e5ca/html5/thumbnails/14.jpg)
Injection and Compression Molded
Property of Alliance LLC