The Influence of the Tantalum Content on the Main Properties of the TixTa9Nb8Zr2Ag Alloy

This study presents the influence of different contents of tantalum alloying elements on the mechanical and electrochemical properties of TixTa9Nb8Zr2Ag alloys and their corrosion resistance in a 3% NaCl solution. These alloys exhibit a structure with more than 80% of the beta phase, a Young's modulus between 82 and 55 GPa close to human bone, and good corrosion resistance, with a corrosion rate between 5 and 47 mu m y(-1). Furthermore, the excellent corrosion behavior of the TixTa9Nb8Zr2Ag alloy with 10 and 15% tantalum content is highlighted, revealed by a nobler corrosion potential, low corrosion rate, and a high passivation tendency in a 3% NaCl solution. The results reported in this work allow us to consider that titanium alloys TixTa9Nb8Zr2Ag with 10-20% Ta could be a valid alternative for use in orthopedic surgery, and the level of tantalum can be customized depending on the nature of the treated bone and the complexity and difficulty of the implant machining, i.e., of the required optimum hardness.