Sm-Co Permanent Magnet

Samarium cobalt permanent magnets

Product overview
Production process
Performance parameters

Product overview

Sintered samarium cobalt permanent magnets are permanent magnet materials composed mainly of metal samarium and metal cobalt, including 1: 5 samarium cobalt magnets and 2: 17 samarium cobalt magnets, divided into two kinds of SmCo5 and Sm2Co17. This material is characterized by its magnetic stability and temperature resistance, as well as its superior resistance to corrosion. With operating temperatures up to 350°C, it is ideal for manufacturing high performance permanent magnet motors and some application products that demand strict operating environments.

Main Properties

Samarium cobalt permanent magnet is made by powder metallurgy. Its chemical composition is SmCo5 and Sm2Co17. It is a magnetic material of which the magnetic properties are second only to NdFeB at present. The advantages of this kind of material lie in its magnetic stability and temperature resistance, as well as its superior corrosion resistance.

It is a rare substitute for sintered NdFeB magnet in special environment. Its disadvantages lie in its hardness and brittleness, as well as the certain limitation in workability.

Production process

01 Alloy Melting

02 Milling by decrepitation

02

03 Press molding

04 Sintering and aging

04

05 Magnetic property test

06 Machining

06

07 Finished product inspection

08 Packing

08 Basic parameters

Parameters
Parameters	Unit		Reference value
Density	g/cm3		8.20 ~ 8.60
Vickers hardness	HV		450 ~ 900
Resistivity	μΩ·m		1.4 ~ 1.6
Compressive strength	MPa		≥650
Bending strength	MPa		≥80
Thermal conductivity	W/(m·K)		8 ~ 10
Young's modulus	GPa		150 ~ 200
Coefficient of thermal expansion	C⊥	10-6/K	11.0~11.2
Coefficient of thermal expansion	C∥	10-6/K	6.9~7.0

main performance

The main magnetic properties of 1:5 type samarium cobalt
Grade	Br		HcB		Hcj		(BH)max		α(Br)	μrec	Tc
Grade	T	kGs	kA/m	kOe	kA/m	kOe	kJ/m3	MGOe	%/K	-	℃
SmCo18	≥0.87	≥8.7	≥637	≥8	≥1353	≥17	135~151	17~19		≤1.05	≥700
SmCo20	≥0.92	≥9.2	≥680	≥8.5	≥1353	≥17	151~167	19~21		≤1.05	≥700
SmCo22	≥0.97	≥9.7	≥709	≥8.9	≥1353	≥17	167~183	21~23		≤1.05	≥700

The main magnetic properties of 2:17 samarium cobalt
Grade	Br		Hcb		Hcj		(BH)max		α(Br)	μrec	Tc
Grade	T	kGs	kA/m	kOe	kA/m	kOe	kJ/m3	MGOe	%/K	--	℃
SmCo24D	≥ 1.01	≥ 10.1	≥ 422	≥ 5.3	≥ 557	≥ 7	183 ~ 199	23 ~ 25	-0.035	--	≥780
SmCo26D	≥ 1.05	≥ 10.5	≥ 438	≥ 5.5	≥ 557	≥ 7	199 ~ 215	25 ~ 27	-0.035	--	≥780
SmCo28D	≥ 1.1	≥ 11	≥ 454	≥ 5.7	≥ 557	≥ 7	215 ~ 231	27 ~ 29	-0.035	--	≥780
SmCo30D	≥ 1.14	≥ 11.4	≥ 477	≥ 6	≥ 557	≥ 7	231 ~ 247	29 ~ 31	-0.035	--	≥780
SmCo32D	≥ 1.17	≥ 11.7	≥ 485	≥ 6.1	≥ 557	≥ 7	247 ~ 263	31 ~ 33	-0.035	--	≥780
SmCo24	≥ 1.01	≥ 10.1	≥ 573	≥ 7.2	≥ 1194	≥ 15	183 ~ 199	23 ~ 25	-0.035	≤1.1	≥800
SmCo26	≥ 1.05	≥ 10.5	≥ 597	≥ 7.5	≥ 1194	≥ 15	199 ~ 215	25 ~ 27	-0.035	≤1.1	≥800
SmCo28	≥ 1.1	≥ 11	≥ 621	≥ 7.8	≥ 1194	≥ 15	215 ~ 231	27 ~ 29	-0.035	≤1.1	≥800
SmCo30	≥ 1.14	≥ 11.4	≥ 644	≥ 8.1	≥ 1194	≥ 15	231 ~ 247	29 ~ 31	-0.035	≤1.1	≥800
SmCo32	≥ 1.17	≥ 11.7	≥ 668	≥ 8.4	≥ 1194	≥ 15	247 ~ 263	31 ~ 33	-0.035	≤1.1	≥800
SmCo22H	≥ 0.97	≥ 9.7	≥ 644	≥ 8.1	≥ 1592	≥ 20	167 ~ 183	21 ~ 23	-0.035	≤1.1	≥820
SmCo24H	≥ 1.01	≥ 10.1	≥ 668	≥ 8.4	≥ 1592	≥ 20	183 ~ 199	23 ~ 25	-0.035	≤1.1	≥820
SmCo26H	≥ 1.05	≥ 10.5	≥ 693	≥ 8.7	≥ 1592	≥ 20	199 ~ 215	25 ~ 27	-0.035	≤1.1	≥820
SmCo28H	≥ 1.1	≥ 11	≥ 724	≥ 9.1	≥ 1592	≥ 20	215 ~ 231	27 ~ 29	-0.035	≤1.1	≥820
SmCo30H	≥ 1.14	≥ 11.4	≥ 756	≥ 9.5	≥ 1592	≥ 20	231 ~ 247	29 ~ 31	-0.035	≤1.1	≥820
SmCo32H	≥ 1.17	≥ 11.7	≥ 773	≥ 9.7	≥ 1592	≥ 20	247 ~ 263	31 ~ 33	-0.035	≤1.1	≥820
SmCo14L	≥ 0.76	≥ 7.6	≥ 501	≥ 6.3	≥ 1194	≥ 15	103 ~ 119	13 ~ 15	-0.005	≤1.1	≥830
SmCo16L	≥ 0.82	≥ 8.2	≥ 541	≥ 6.8	≥ 1194	≥ 15	119 ~ 135	15 ~ 17	-0.008	≤1.1	≥830
SmCo18L	≥ 0.87	≥ 8.7	≥ 573	≥ 7.2	≥ 1194	≥ 15	135 ~ 151	17 ~ 19	-0.01	≤1.1	≥830
SmCo20L	≥ 0.92	≥ 9.2	≥ 605	≥ 7.6	≥ 1194	≥ 15	151 ~ 167	19 ~ 21	-0.02	≤1.1	≥830
SmCo22L	≥ 0.97	≥ 9.7	≥ 637	≥ 8	≥ 1194	≥ 15	167 ~ 183	21 ~ 23	-0.02	≤1.1	≥830
SmCo24L	≥ 1.01	≥ 10.1	≥ 668	≥ 8.4	≥ 1194	≥ 15	183 ~ 199	23 ~ 25	-0.02	≤1.1	≥830
SmCo26L	≥ 1.05	≥ 10.5	≥ 692	≥ 8.7	≥ 1194	≥ 15	99 ~ 215	25 ~ 27	-0.025	≤1.1	≥830

Note: D in the grade stands for low coercive force products, H stands for high coercive force products, and L stands for low temperature coefficient products.