Low temperature resistivity studies of Fe–Cr–Sn alloys in alpha and sigma phases

Abstract

Abstract Low-temperature resistivity measurements were carried out on a set of FeCrSn samples with Sn concentrations of 1, 2 and 3.5 at% and structures ranging from pure α-phase to heavy α/σ mixing up to an almost pure σ-phase. 57 Fe Mossbauer spectroscopy was used to characterize the samples and to evaluate the fraction of the σ-phase present in each. The α–σ transformation is easily observed by electrical resistivity since the thermal variations of ρ are very sensitive to α and σ phases. It was observed that with increasing Sn concentration the increase of ρ with temperature is sharper in the σ phase, and is smaller in the α phase. This is explained in terms of the role of Sn in the microstructure of FeCrSn alloys.