Magnetocrystalline anisotropy in Fe–Mn–Ga magnetic shape memory alloy

Magnetocrystalline anisotropy of the martensite phase was investigated in a single crystal of Fe44Mn28Ga28 shape memory alloy. It was found that the martensite phase of Fe44Mn28Ga28 alloy has a tetragonal distorted L21 structure, with a = 0.5368 nm and c = 0.7081 nm. An approximately single variant was obtained by thermomechanical treatment, and magnetization measurement revealed that the c-axis is the magnetic easy axis. The magnetocrystalline anisotropy constant Ku was determined to be 7.6 × 105 J m−3 at 300 K.