Sm₂(Fe_0.8Co_0.2)N_3.03圧縮成形ボンド磁石の磁気余効

抄録

The magnetic field and temperature dependences of the magnetic aftereffect constant S_v were examined for the Sm₂(Fe_0.8Co_0.2)₁₇ N_3.03 compression bonded magnet at a temperature range from 77 to 397K. Sv increases gradually with increasing the magnetic field. The temperature dependence of coercive force H_CJ, for Sm₂(Fe_0.8Co_0.2)₁₇N_3.03, Sm-Co and Nd-Fe-B magnets decrease with the increasing temperature. However, the temperature dependence of Sv for the Sm₂(Fe_0.8Co_0.2)₁₇N_3.03 compression bonded magnet was reverse to H_CJ, in contrast to Sm-Co and Nd-Fe-B magnets. The temperature variation of coercive force ΔH_CJ/ΔT in these rare-earth magnets linearly decreases as the activation volume v increases. Larger v for low ΔH_CJ/ΔA T values and smaller v for higher H_CJ, values are necessary, so that balanced performance of H_CJ, should be obtained by choosing appropriate v values.