Spin configuration and magnetostrictive properties of Laves compounds TbₓDy₀.₇₋ ₓPr₀.₃(Fe₀.₉B₀.₁)₁.₉₃ (0.10≤x ≤ 0.28)

Abstract

The spin configuration and magnetostrictive properties of TbₓDy₀.₇₋ ₓPr₀.₃(Fe₀.₉B₀.₁)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[sub c] and spin reorientation temperature T[sub 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[sub c] increases from 617 to 623 K, while T[sub 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 K₁ and the ratio λα/K₁ reach a minimum and a maximum value at x=0.22, respectively. The single phase Tb₀.₂₂Dy₀.₄₈Pr₀.₃(Fe₀.₉B₀.₁) ₁.₉₃ compound has the lowest magnetocrystalline anisotropy, the highest magnetostriction to anisotropy ratio, and a large spontaneous magnetostriction λ₁₁₁of ~ 1500 ppm at room temperature. In view of these properties, the compound is a promising magnetostrictive material.