ZnボンドSm₂Fe₁₇N_x磁石作製過程における寸法変化とFe-Zn相生成

抄録

The sintering behavior of the compacts composed of Sm₂Fe₁₇N_x and 30wt%Zn was studied by DSC, the dilatometric measurement and XRD, and the magnetic properties of the sintered compacts were also investigated by using VSM. The dilatometric measurement revealed that the compacts exhibit an expansion beginning at 643K during sintering, and it was confirmed that this expansion was due to the formation of FeZn₄ and/or Fe₃Zn₇. The results of VSM show that magnetic properties were improved with the increase of heat treatment temperature from 623K ; the optimum coercivity(_iH_c) of 0.948T was obtained by the heat treatment at 747K for 4h. Beyond 763K, however, the magnetic properties decreased due to the decomposition of Sm₂Fe₁₇N_x into α-Fe and SmN.