Fabrication, structural, and magnetic characterization of ni 41.7 mn 47.7sn 10.6 glass-coated microwires

Abstract

Heusler-type Ni–Mn–Sn glass-coated microwires (mws) with the average chemical composition Ni41.7Mn47.7Sn10.6 were prepared by the Taylor–Ulitovsky technique; a basic characterization of their structural, microstructural, and magnetic properties is presented. Polycrystalline mws samples had a nearly uniform circular cross section with an average diameter of around 200 μm and a microstructure formed by micronic in size globular in shape grains. X-ray diffraction (XRD) analysis shows that the as-prepared samples crystalize into a highly ordered L21 -type austenitic crystal structure with a lattice parameter a = 5.96 Å. However, the thermomagnetic analysis curves, which were measured under a low magnetic field of 10 mT, denote the occurrence of two successive magnetic transitions at 248 and 265 K which leads to a broad thermal dependence of the magnetic entropy change.