Composition anisotropy compensation and spontaneous magnetostriction in Tb0.2Dy0.8−xPrx(Fe0.9B0.1)1.93 alloys

Abstract

The possibility of the composition anisotropy compensating in Dy1−xPrxFe2 is discussed phenomenologically, based on a single ion approach. The crystal structure, the easy magnetization direction, and the spontaneous magnetostriction of Tb0.2Dy0.8−xPrx(Fe0.9B0.1)1.93 (0⩽x⩽0.7) alloys are studied. Single-phase Tb0.2Dy0.8−xPrx(Fe0.9B0.1)1.93 with cubic MgCu2-type structure forms up to x=0.4 and the magnetostrictive phase exists in all the alloys studied. A single (440) peak of x-ray diffraction of the Laves phase exists when 0⩽x⩽0.3, but becomes doubly split when 0.4⩽x⩽0.7 because of a large spontaneous magnetostriction along its easy magnetization direction 〈111〉. Composition anisotropy compensation is realized in Tb0.2Dy0.8−xPrx(Fe0.9B0.1)1.93 alloys. Tb0.2Dy0.4Pr0.4(Fe0.9B0.1)1.93 alloy with the single Laves phase has a large magnetostriction (λ111≈1200 ppm) and a low anisotropy, which may be a good candidate material for magnetostriction application.