Effect of 3d transition metal additions on the phase constituent, mechanical properties, and shape memory effect of near–eutectoid Ti–4Au biomedical alloys

Abstract

Shape memory alloys (SMA) are important topics among the urgently demanded biomaterial and medical application issues. A series of promising near–eutectoid Ti–4 at.% Au–5 at.% X (X = 3d transition metals: V, Cr, Mn, Fe, Co, Ni, and Cu) alloys was systematically studied in this study. Specimens were prepared by physical metallurgy method and were analyzed by XRD, bending test, Vickers hardness, and tensile test. The additional third elements of Cr and Mn clearly showed shape memory effect. On the other hand, when the additional third elements were V, Cr, Mn, and Mo, the ternary alloys performed slight pseudoelasticity or limited superelasticity while there was no superelasticity observed as the third elements were Fe and Co. According to the investigation of fundamental mechanical properties, the additional third elements of Cr and Mn, which are classified as the optimized group, are superior to other alloys based on the evaluations of their strength, ductility, shape memory effect, and superelastic effect. This study systematically screened the influences of the 3d transition metals on the near–eutectoid Ti–4 at.% Au–5 at.% X alloys. The results can be a database and a guideline for the further specimen preparations and investigations for the future research.