Microstructure and mechanical behavior of Ti25Nb25Zr alloy prepared from pre-alloyed and hydride-mixed elemental powders

Abstract

A study has been undertaken on the feasibility of the powder-metallurgy manufacturing process to fabricate β-type Ti25Nb25Zr alloy (mass%) for biomedical applications. The Ti25Nb25Zr alloy was fabricated from a mixture of TiH2 with constituent elemental powders, and from a pre-alloyed Plasma Rotating Electrode Processed (PREP) Ti25Nb25Zr powder, separately. It is shown that different processing methods led to different microstructures and mechanical properties. The Ti25Nb25Zr compact prepared by pre-alloyed powder exhibits poor strength whereas TiH2 processed Ti25Nb25Zr compact exhibits comparatively ultra-fine grained microstructure with significantly improved strength. The proposed fabrication method may have several opportunities to fabricate metallic alloys with enhanced mechanical properties.