Fabrication of biomedical Ti–35Nb–7Zr–5Ta alloys by mechanical alloying and spark plasma sintering

Abstract

Ti–35Nb–7Zr–5Ta biomedical alloys were fabricated by spark plasma sintering of nanocrystalline powders by mechanical alloying. After 60 h milling, mixtures of respective elemental powders transformed into a homogeneous structure of completed β-Ti solid solution. The grain size of the milled powder was ∼9 nm. Subsequently, the obtained nanosized grained powder was consolidated into bulk form by spark plasma sintering at different sintering parameters. At a sintering temperature of 1373 K, the fabricated bulk alloys reached nearly full density. The microstructure of the fabricated alloys was of hcp α-Ti regions surrounded by bcc β-Ti regions. In addition, fracture strengths, Young's modulus and microhardness of the fabricated alloys were investigated to explore the potential adaptability of the fabricated alloys as human implant.