Martensitic transition, structural and magnetoresistive properties of shape memory Heusler melt spun ribbons

Abstract Here, we report the martensitic transition, low temperature structural and magnetoresistive properties of Mn rich Mn-Ni-Sn shape memory Heusler melt spun ribbons. They have been prepared by melt spinning technique. Present ribbons exhibit the first order magneto-structural (i.e. called martensitic) transition below room temperature (RT) from cubic austenite phase to the monoclinic martensite phase. The room temperature as well as low temperature structure is studied using XRD. These results also corroborate with the microstructural analysis at RT, where no elongated thin plates/strips, corresponding to the martensitic phase twin variants are found inside the grains. They have been found to show maximum negative MR (around −11%) around the martensitic transition. The magnetic field dependent MR at different temperatures in the vicinity of martensitic transition has also been studied for the present ribbons.