The effect of Ni on the growth morphology of primary β-phase in an In-35 wt%Sn alloy

Abstract

In-35 wt%Sn alloy is a superconductive alloy and its superconductivity is highly dependent on the properties of the β-In3Sn phase. However, detail solidification behaviour with microstructure development had not been studied with minor element additions. This paper investigates the effect of minor addition of Ni on the β-phase evolution in an In-35 wt%Sn alloy during the solidification process using the in-situ real-time synchrotron radiography technique. The β-phase preferably formed a columnar dendritic structure that made a transition to a mix structure of cellular and dendrite with a unique morphology with an addition of 0.05 wt%Ni. The findings provide detailed observations of microstructure evolution, specifically β-In3Sn phase, and examine the effects of Ni addition during solidification of the In-35 wt%Sn alloy, as well as the thermal properties of the alloys by differential scanning calorimeter.