Degradation of titanium and its alloys

Abstract

This chapter summarizes the state-of-the-art knowledge on the degradation modes of Ti and biomedically relevant Ti-based alloys. First, general aspects of passivity of Ti as well as special corrosion modes of passive Ti are shortly described. Then, the influence of alloying on the electrochemical dissolution modes is summarized, emphasizing the specific corrosion modes relevant for the biomedical application. Degradation of materials in biomedical applications can, in addition to purely chemical or electrochemical processes, be strongly influenced by mechanical/tribological processes. Therefore, tribocorrosion of Ti and Ti-based alloys is described. In addition, the role of the biological environment in the degradation process of Ti alloys is discussed. Moreover, a short discussion on some relevant implant design-related aspects of degradation is provided.