Microstructure and Mechanical Behavior of Ti-25Nb-25Zr Alloy Prepared from Pre-Alloyed and Hydride-Mixed Elemental Powders

A study has been undertaken on the feasibility of the powder-metallurgy manufacturing process to fabricate beta-type Ti-25Nb-25Zr alloy (mass%) for biomedical applications. The Ti-25Nb-25Zr alloy was fabricated from a mixture of TiH2 with constituent elemental powders, and from a pm-alloyed Plasma Rotating Electrode Processed (PREP) Ti-25Nb-25Zr powder, separately. it is shown that different processing methods led to different microstructures and mechanical properties. The Ti-25Nb-25Zr compact prepared by pre-alloyed powder exhibits poor strength whereas TiH2 processed Ti-25Nb-25Zr 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.