Mechanical properties of Ti-(∼49 at%) Ni shape memory alloy: Part I. Effect of cold deformation

The present investigation aims to study the effect of cold deformation on the mechanical properties and shape recovery behavior of the Ti-rich Ti-Ni alloy. The micrographic investigations and XRD analyses have revealed that the microstructure of the homogenized and quenched samples comprises austenite (B2) and martensite (B19′) phases. Significant enhancement of martensite volume fractions in the microstructure has been achieved after 30% cold deformation. The effect of deformation has also been manifested in terms of the sloping tensile curve in the region of shape memory strain. The shape recovery experiment has indicated improved shape recovery ratio in the case of the deformed samples owing to the delay in onset of the plastic straining during the shape deformation.