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Charts/graphs reference typical magnet performance. Further reading about Samarium Cobalt Magnets

Grade
(click to view
demagnetization
curve)
Max Energy
Product
Residual
Induction
Min Intrinsic
Coercivity
Coercivity 
Max Operating
Temp
Curie Temp
Coefficient
Induction
20-150°C
Coefficient
Coercivity
20-150°C
BHmax Br Hci Hc Tmax Tc α β
MGOe kG kOe kOe °C °C % / °C % / °C
Type 2:17
S3010
30
11.2
10
9.2
300
825
-0.03
-0.17
S2610
26 10.5
10
8.8
300
825
-0.03
-0.17
S3212
32
11.5
12
10.0
300
825
-0.03
-0.17
S3012
30
11.3
12
9.8
300
825
-0.03
-0.17
S2612
26
10.6
12
9.4
300
825
-0.03
-0.17
S2212
22
9.9
12
9.0
300
825
-0.03
-0.17
S3215
32
11.5
15
10.5
300
825
-0.03
-0.22
S3015
30
11.3
15
10.3
300
825
-0.03
-0.22
S2816
28
11.0
16
10.3
300
825
-0.03
-0.22
S2616
26
10.8
16
10.1
300
825
-0.03
-0.22
S3218
32
11.6
18
10.8
300
825
-0.03
-0.22
S3018
30
11.3
18
10.6
300
825
-0.03
-0.22
S2618
26
10.7
18
10.1
300
825
-0.03
-0.22
S2820
28
11.0
20
10.4
300
825
-0.03
-0.22
S2620
26
10.8
20
10.3
300
825
-0.03
-0.22
S3022
30
11.3
19
10.5
300
825
-0.03
-0.22
S2825
28
11.1
25
10.5
300
825
-0.03
-0.22
S2625
26
10.8
25
10.2
300
825
-0.03
-0.22
S2425
24
10.3
25
9.8
350
825
-0.03
-0.22
S2225
22
9.7
25
9.2
350
825
-0.03
-0.22
S2830
28
11.0
30
10.5
350
825
-0.03
-0.22
S2630
26
10.8
30
10.3
350
825
-0.03
-0.22
S2430
24
10.3
30
9.8
350
825
-0.03
-0.22
S2230
22
9.7
30
9.3
350
825
-0.03
-0.22
S2435
24
10.3
35
9.9
350
825
-0.03
-0.22
S2235
22
9.7
35
9.3
350
825
-0.03
-0.22
Type 1:5
S2415
24
10.0
15
9.3
250
750
-0.05
-0.22
S2215
22
9.5
15
8,8
250
750
-0.05
-0.22
S2418
24
10.0
18
9.4
250
750
-0.05
-0.22
S2218
22
9.5
18
9.0
250
750
-0.05
-0.22
S2018
20
9.0
18
8.5
250
750
-0.05
-0.22
S1818
18
8.6
18
8.2
250
750
-0.05
-0.22
S2220
22
9.5
20
9.1
250
750
-0.05
-0.22
S2020
20
9.0
20
8.6
250
750
-0.05
-0.22
S1820
18
8.6
20
8.2
250
750
-0.05
-0.22
S2223
22
9.5
23
9.1
250
750
-0.05
-0.22
S2025
20
9.0
25
8.6
250
750
-0.05
-0.22
S1825
18
8.6
25
8.2
250
750
-0.05
-0.22
S2030
20
9.0
30
8.6
250
750
-0.05
-0.22

 

Typical Physical Properties - Type 2:17
Curie Temperature  800 - 825°C
*Coefficient of Thermal Expansion - Perpendicular to magnetization orientation +11.0 - +12.0 x 10-6 °C-1
*Coefficient of Thermal Expansion - Parallel to magnetization orientation  +9.0 - +10.0 x 10-6 °C-1
 Electrical Resistivity  80 - 90 µΩ·cm
 Density  8.3 - 8.4 g·cm-3
 Vicker's Hardness  550 - 650 HV
 Young's Modulus  140 - 150 kN·mm-2
 Bending Strength  0.09 - 0.15 kN·mm-2
 Compressive Strength  0.65 - 0.80 kN·mm-2

*Due to magnetostriction, all magnetic materials expand/contract at different rates, depending on magnetic orientation.

 

Typical Physical Properties - Type 1:5
Curie Temperature  720 - 750°C
*Coefficient of Thermal Expansion - Perpendicular to magnetization orientation  +12.0 - +13.0 x 10-6 °C-1
*Coefficient of Thermal Expansion - Parallel to magnetization orientation  +6.0 - +7.0 x 10-6 °C-1
 Electrical Resistivity  50 - 60 µΩ·cm
 Density  8.2 - 8.3 g·cm-3
 Vicker's Hardness  550 - 650 HV
 Young's Modulus  100 - 110 kN·mm-2
 Bending Strength  0.12 - 0.18 kN·mm-2
 Compressive Strength  0.9 - 1.0 kN·mm-2

*Due to magnetostriction, all magnetic materials expand/contract at different rates, depending on magnetic orientation.

About Samarium Cobalt

As the first commercially viable rare earth permanent magnet material, Samarium Cobalt (Sm-Co) is considered to still be the premium material for many high performance applications. Formulated in the 1960's, it came as a revolutionary product, initially tripling the energy product of other materials available at the time.

Sm-Co materials come in energy products from 16 MGOe up to 33 MGOe. Their high resistance to demagnetizing influences and excellent thermal stability has ensured Sm-Co as the premium choice for the most demanding motor applications. In addition, the corrosion resistance is significantly higher than, for example, Nd-Fe-B. It is still recommended to coat the magnet in acidic conditions. Its corrosion resistance has also offered a high degree of comfort to those looking to use magnets in medical applications.

On a 'per pound' basis, Sm-Co is the most expensive permanent magnet material. However, because of its high energy product, it has achieved considerable commercial success by decreasing the required volume of magnet material to fulfill a certain task. Sm-Co can typically be used up to 300 °C, though, of course, its actual performance at that temperature is governed strongly by the design of the magnetic circuit. As with all permanent magnet materials, extreme caution must be exercised when handling magnetized samples. Sm-Co can be prone to chipping and should not be used a structural component in an assembly.