Effect of gold addition on the microstructure, mechanical properties and corrosion behavior of Ti alloys

Abstract

We performed a systematic investigation of the Ti-xAu (x∈=∈5, 10, 15, 20, and 40 wt%) alloys to assess the effect of addition of element Au on the microstructure, mechanical properties, and corrosion behavior of commercially pure titanium (cp-Ti). The phase and microstructure were characterized using X-ray diffraction (XRD), optical microscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results indicated that the Ti-xAu alloys containing up to 15 wt% Au showed a hexagonal close-packed α-Ti structure, whereas the Ti-xAu alloys containing more than 20 wt% Au were mainly composed of the α-Ti phase and Ti3Au intermetallic phase. We also investigated the effect of alloying element Au on the mechanical properties (including Vickers hardness and modulus) and corrosion behavior of Ti-xAu binary alloys. The addition of gold to Ti improved its hardness. Electrochemical results showed that the Ti-xAu alloys exhibited improved corrosion resistance than cp-Ti. © 2014 The Author(s).