Effect of substitution of Mn with Fe or Cr in Heusler alloy ofCo2MnSn

Abstract

Crystallographic and magnetic properties ofCo2Mn1−xFexSn and Co2Mn1−yCrySn Heusler alloys were studied using x-ray diffraction, scanning electron microscopy withenergy dispersive x-ray analysis, magnetization measurements and Mössbauer spectroscopy.We found that the intermetallic compounds crystallize into a single phase with theL 21-type Heusler structure at the concentration of0≤x≤0.5 for Co2Mn1−xFexSn and 0≤y≤0.3 for Co2Mn1−yCrySn. The spontaneous magnetization increases when Mn is substituted with Fe and decreaseswhen Mn is substituted with Cr. The values of hyperfine field at the Sn nuclear sites inCo2Mn1−xFexSn and Co2Mn1−yCrySn also increase or decrease in combination with the size of magnetization. Thesemeasurements suggest that the Slater–Pauling behaviour in half-metallic full-Heusleralloys provides a good description of the substitution effect of Mn with Fe or Cr.