Effect of cooling rate on the phase transformations behavior and hardness of NiTi shape memory alloys

Abstract EN

NiTi alloy is well- known shape memory alloys and has been widely used for bio-medical, mechanical and electrical applications.

In this study, a Ni-rich porous NiTi alloys are produced by powder metallurgy technique.

Three samples of these alloys were cooled in three media: furnace, water, and ice bath.

X-ray diffraction (XRD) was used in the study as characterization techniques, hardness measurement and shape memory effect (SME) properties were carried out to investigate the effect of cooling rate on phases and mechanical properties.

XRD test shows that the sintered samples consist of three phases at room temperature (NiTi monoclinic phase, NiTi cubic phase and Ni3Ti hexagonal phase) .The results show the correlation between cooling rate and properties of the alloy.