Spin reorientation and first-order magnetization processes in (Er1-xTbx)2Fe14B

Magnetic properties of the quasi-binary system (Er1-xTbx)2Fe14B have been studied between 6 and 300 K using steady magnetic fields up to 150 kOe. Successive transitions were observed for the samples with x≤0.4, which are interpreted as the spin reorientation among the three phases in which the direction of the total magnetization is (i) parallel to the [001] axis, (ii) parallel to the [100] axis, and (iii) within the (010) plane, respectively. The first-order magnetization process was observed in the samples with x=0.3, 0.4 and 0.45. These results were elucidated by simple-mixture model including the crystalline electric field and exchange field interactions. (orig.)