Biomedical Ti-24Nb-4Zr-7.9Sn alloy fabricated by conventional powder metallurgy and spark plasma sintering

摘要

Ti-24Nb-4Zr-7.9Sn alloy was prepared by Powder Metallurgy (PM) and Spark Plasma Sintering (SPS) using titanium hydride powder, niobium powder, zirconium powder and tin powder as raw materials. The effect of sintering process on microstructure and mechanical properties was investigated by mechanical measurement and SEM. The results showed that the best sintering process by PM was at 1250°C for 2 h. The relative density, tensile strength and elongation of the alloy reached 97.2%, 705MPa and 6.2%, respectively. The microstructure was a typical Widmannstatten microstructure, which possessed (3-matrix and a-precipitation. The best process by SPS was at 1250°C. The relative density, tensile strength and elongation of the alloy sintered by SPS reached 99.4%, 788.5MPa and 6.4%, respectively. The grain size was about 100ìm and the microstructure was uniform. The fracture morphology of the alloy was ductile rupture. Compared to PM, Ti-24Nb-4Zr-7.9Sn alloy fabricated by SPS exhibited better comprehensive properties and more uniform microstructure.