Effect of Oxygen in the Structure, Microstructure and Mechanical Properties of Ti-xNi (x = 5, 10, 15 and 20 wt%) Alloys

Titanium alloys have great potential for use as biomaterials due to good biocompatibility and mechanical properties. The nickel addition to titanium improves the wear, corrosion and mechanical resistance of this element. The objective of this paper was to investigate the effects of oxygen on the structure, microstructure and some selected mechanical properties of this alloy system. The results showed that the samples present the adequate nickel concentration and low concentration of other metals. The alloys exhibit predominantly the &alpha
and intermetallic Ti2Ni phases, and the amount of it increases according to the nickel concentration. In the Ti-15Ni and Ti-20Ni alloys, this intermetallic reacted with oxygen forming Ti4Ni2O trioxide. The microstructures varied according to the processing, as well as the microhardness values. Elastic modulus values are slightly above titanium due to the formation of a new intermetallic phase but have not varied significantly with processing and doping with oxygen.