Nanomechanical response of martensite in Ti-(∼49 at.%) Ni alloy

Influence of ageing on the mechanical behavior of near-equiatomic NiTi alloy has been studied at microstructural scale by nanoindentation technique. Hardening of the martensite plate has been estimated by conducting cyclic indentation with incremental loads at the fixed location of martensite. It has been found that maximum shape recovery is achieved at the peak aged condition. This has been attributed to the delayed onset of plasticity. Peak micro and nanohardness has been attained after ageing for 60 min at 400 °C.

► Effect of ageing on mechanical behavior of Ti-(∼49 at.%) Ni by nanoindentation. ► Hardening of martensite was measured by cyclic indentation with incremental loads. ► Nanoindentation response of martensite was maximum at peak aged condition. ► Cold deformation followed by ageing has improved the shape recovery response.