Wear mechanisms of nitinol under reciprocating sliding contact

It has been recently found that nitinol (TiNi) alloy has superior wear resistance compared to other conventional materials. The stress-induced martensite transformation exhibited by this alloy contributes to its high wear resistance. Nitinol is characterized by shape memory and superelastic effect which occur due to reversible martensite transformation. The superelastic effect of TiNi alloy is characterized by large recoverable deformation associated with the reversible stress-induced martensite transformation. Understanding the tribological properties of superelastic TiNi under reciprocating wear helps to increase its utilization in application where high wear is expected. In the present study the tribological behavior of superelastic TiNi is studied using reciprocating wear tests. Wear tests were performed under various normal loads and frequencies. The effect of normal load, frequency and sliding distance on wear behavior of superelastic TiNi is investigated. Several effects were found to control the wear response under a range of normal load and reciprocating frequency. Abrasion, adhesion and delamination mechanisms were identified during wear.