The effects of short-time solution treatment and short-time aging on mechanical properties of Ti-6Al-4V for orthopaedic applications

Abstract

The Ti-6Al-4V alloy is currently utilized as structural materials in artificial hip and knee joints, bone plates and screws, and artificial dental roots. It is mainly used in implants that replace hard tissue because has a high strength, good corrosion resistance, high biocompatibility compared to other conventional metallic biomaterials such as stainless steel and Co-Cr-Mo alloys. The Ti-6Al-4V alloy with low Young's modulus equivalent to that of the cortical bone is a simultaneously required in order to inhibit bone absorption. By short-time solution treatment and subsquent short-time aging, the mechanical properties of Ti-6Al-4V alloy can be improved while maintaining a low Young's modulus. The result showed optimum heat treatments were solution treatment at 930 oC (1203 K) for 60 s and subsquent aging at 530 oC (803 K) for 40 s; the yield strength and tensile strength improved without reduction in ductility. Their maximum improvement rates of reached 21,6% and 21,1%, respectively and the Young's modulus reduced with maximum rates of reached 12%.