Magnetic Anisotropy in Dysprosium

Torque measurements have been made on single-crystal dysprosium. The constant K1 was determined in the paramagnetic region, and also in the antiferromagnetic region, where the transition to ferromagnetism appeared as a large distortion in the torque curves. From the data in the paramagnetic region the saturation value of K1 is predicted as 1.1×108 ergs g−1. The constant K4 was determined in the ferromagnetic region, and changes in sign were observed at field strengths close to the critical value. The changes in easy direction for magnetization are compared with the behavior of the magnetostriction of dysprosium.