Two different microstructures of NieTieFe shape memory alloys processed through different thermomechanical treatments with nearly similar grain size and in-grain misorientation but different crystallographic textures were subjected to series of thermal cycles without external loading. The microstructures and the phase transformation behavior of the samples were examined after every seventy
cycles. The experiment involved treating the samples with liquid nitrogen (LN2) for complete martensitic
(B190
) transformation and then heating it back to parent austenite (B2) condition. Thermal cycling
introduced significant differences in microstructural parameters especially the grain boundary nature,
stored elastic energy and the misorientation or defect densities. These microstructural alterations during
thermal cycling were related to changes in transformation temperatures and enthalpy. Thermal cycling
also brought out changes in crystallographic orientations of austenite grains. The present study aims to
address the role of microstructure on the thermal fatigue behavior in NieTi based shape memory alloys
during cyclic transformations