SmCo5 Magnet

In 1966, Hoffer reported that YCo5 has a relatively large crystal anisotropy with a single easy axis of magnetization. Then Strnat reported a (BH)max of 40.6kJ/m3 for SmCo5 in 1967. Further improvement in (BH)max to 144.7kJ/m3 was reported in 1968 by Buschow. Discovery and development of SmCo5 magnet marked the arrival of the rare earth magnet. Thereby, SmCo5 magnet is generally known as the first generation of rare earth permanent magnetic material. Cobalt content in SmCo5 magnet is around 66wt% and thus accused of raw material cost. In addition, SmCo5 magnet had better machinability in comparison to Sm2Co17 magnet.

Magnetic Properties of SmCo5 Magnet

Grade Remanence

Br

 Coercivity

Hcb

 Intrinsic Coercivity

Hcj

 Max. Energy Product

(BH)max

 Curie Temp.

Tc

 Max. Ope. Tem.

Tw

 Temp. Coeff. of Br Temp. Coeff. of Hcj
T kGs kA/m kOe kA kOe kJ/m3 MGOe ℃ ℃ %/℃ %/℃
RECo5-16S 0.79-0.84 7.9-8.4 620-660 7.8-8.3 ≥1830 ≥23.0 118-135 15-17 750 250 -0.035 -0.28
RECo5–18S 0.84-0.89 8.4-8.9 660-700 8.3-8.8 ≥1830 ≥23.0 135-151 17-19 750 250 -0.040 -0.28
RECo5–20S 0.89-0.93  8.9-9.3 684-732 8.6-9.2 ≥1830 ≥23.0 150-167 19-21 750 250 -0.045 -0.28
RECo5–22S 0.92-0.96  9.2-9.6 710-756 8.9-9.5 ≥1830 ≥23.0 167-183 21-23 750 250 -0.045 -0.28
RECo5–24S 0.96-1.00  9.6-10.0 740-788 9.3-9.9 ≥1830 ≥23.0 183-199 23-25 750 250 -0.045 -0.28
LTC(RECo5-10) 0.62-0.66 6.2-6.6 485-517 6.1-6.5 ≥1830 ≥23.0 75-88 9.5-11.0 750 300 20-100℃: +0.0156

100-200℃: +0.0087

200-300℃: +0.0007

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  • The above-mentioned data of magnetic properties and physical properties are given at room temperature.
  • The max working temperature of magnet is changeable due to length-diameter ratio, coating thickness and other environment factors.