Novel beta-type high entropy shape memory alloys with low magnetic susceptibility and high biocompatibility

Abstract

In order to develop novel superelastic alloys with low magnetic susceptibility and high biocompatibility, (TiZrHf)-NbTaAl alloys with multi principal elements were designed and the effect of Al content on shape memory properties was investigated. The stress induced martensitic transformation was confirmed to occur upon loading. Both superelasticity and shape memory effect could be achieved by the adjustment of Al content. A (TiZrHf)(82)Nb5Ta5Al8 alloy exhibited a large superelastic strain of 3.2%. The (TiZrHf)(82)Nb5Ta5Al8 alloy revealed a low magnetic susceptibility less than half of those of Ti-Ni and Ti-based alloys. The (TiZrHf)(82)Nb5Ta5Al8 alloy also showed excellent corrosion resistance and biocompatibility similar to those of pure Ti.