Observation of field-induced reverse transformation in ferromagnetic shape memory alloy Ni50Mn36Sn14

Abstract

The structural and magnetic properties of the ferromagnetic Heusler alloy Ni50Mn36Sn14 were studied by magnetization and x-ray powder diffraction measurements in fields up to 5T. The alloy undergoes the martensitic transformation from the L21-type cubic structure with the lattice parameter ac=0.5988nm into an orthorhombic structure with the lattice parameters ao=0.8617nm, bo=0.5702nm and co=0.4359nm at Ms=220K with a thermal hysteresis of 40K. The cell volume contracts by 0.37% and the magnetic moment decreases by 50% at Ms. Furthermore, we directly observed the field-induced reverse martensitic transformation.