Changes of thermal hysteresis during homogenisation process of Ni-Mn-Ga polycrystalline alloy

Abstract

In this paper we present results of the investigation of polycrystalline Ni52,2Mn21,3Ga26,5 alloy before and after homogenisation at 1173K processed for different time intervals. We investigated the influence of duration of homogenisation on kinetics of reversible martensitic transformation (RMT). In order to present changes of kinetics of RMT, thermal hysteresis was determined based on calorimetric (DSC) investigation. Our results suggested that thermal annealing at 1173K caused plastic deformation of crystal lattice in the investigated alloy.