Magnetocrystalline Anisotropy in a Single Crystal Fe-Ni-Ga Ferromagnetic Shape Memory Alloy

Abstract

In order to discuss the advent of the magnetic-field-induced strains for a single crystal Fe22.0Ni51.5Ga26.5 shape memory alloy, the magnetic easy axis in the 14 M martensite phase and the magnetocrystalline anisotropy constant K have been investigated. From the data on the spontaneous thermal expansion and the magnetization curves, the magnetic easy axis of the 14 M martensite phase was determined to be the [010]14 M. The value of K in the martensite phase was estimated to be 1.3×105 J/m3, implying to exhibit a large value of the magnetic-field-induced strain.