بررسي اثر حافظه داري بر روي سطح سايش آلياژ حافظه دار NiTi

Study of shape memory effect on the wear surface of a NiTi shape memory alloy

NiTi alloys are well-known for the shape memory and superelastic effects. There have been extensive researches on effect of psudoelasticity on the wear behavior of these alloys. However, there is no study on the effect of shape memory on the tribological behavior of these alloys. In this work, the shape memory characteristic of Ti-50.3 at% Ni alloy on its tribological behavior was studied. The phase transformation temperatures, was measured by differential scanning calorimetry (DSC). To characterize the shape memory effect of NiTi alloy, a three-point bending test was performed. Wear test was performed on a pin-on-disk tribometer. In order to evaluate the shape memory effect on the wear surface, the surface profilometry of the wear track was obtained after the wear test and also following heating the sample to its austenitic transformation temperature. The results showed that due to the transition of martensite to austenite upon heating, there was about 20% recovery on the deformation of the wear track area.