Magnetic-field-induced strains in polycrystalline Mn1-xCux(0.1≤x≤0.3) alloys

Magnetic-field-induced strain(MFISs) in polycrystalline Mn1-xCux(0.1≤x≤0.3, atomic fraction) alloys are studied by means of X-ray, photomicrograph, DSC, resistance strain gauge method at room temperature. The results show that Mn1-xCux alloys consist of fcc (γ) and fct (γ’) phases after a long period of homogenization because of fcc(γ)→fct(γ’) martensitic transformation in the cooling process. The volume proportion of γ’ phase increases with the increase of Mn content, so that the samples possess much better MFIS performance. At room temperature, the MFIS in Mn0.9Cu0.1 sample reaches 91 ppm in 0.9 T magnetic field.