Spin configuration and magnetostrictive properties of Laves compounds Tb_xDy_(0.7-x)Pr_(0.3)(Fe_(0.9)B_(0.1))_(1.93)(0.10≤ x≤0.28)

摘要

The spin configuration and magnetostrictive properties of Tb_xDy_(0.7-x)Pr_(0.3)(Fe_(0.9)B_(0.1))_(1.93) (0.10 ≤x ≤0.28) Laves compounds are investigated. The spin phase diagram for the compounds is constructed to illustrate both the composition dependence of the Curie point T_C and spin reorientation temperature T_(SR) and the arrangement for the easy magnetization direction (EMD). It is found that when x is increased from 0.16 to 0.28, T_C increases from 617 to 623 K, while T_(SR) decreases from 375 to 160 K at which the EMD reorients from < 100 > to < 111 > axis. The magnetization and magnetostriction of the compounds are measured as a function of applied field. The magnetocrystalline anisotropy constant K_1 and the ratio λ_a/K_1 reach a minimum and a maximum value at x=0.22, respectively. The single phase Tb_(0.22)Dy_(0.48)Pr_(0.3)(Fe_(0.9)B_(0.1))_(1.93) compound has the lowest magnetocrystalline anisotropy, the highest magnetostriction to anisotropy ratio, and a large spontaneous magnetostriction λ_(111) of ～1500 ppm at room temperature. In view of these properties, the compound is a promising magnetostrictive material.