Lowering of elastic modulus in the near-beta Ti–13Nb–13Zr alloy through heat treatment

Abstract

The bio-implant devices require adequate strength and low elastic modulus, for compatibility with human bone. In this study, the near-beta Ti–13Nb–13Zr alloy was subjected to two different solutionising temperatures and quenched at different temperatures. Microstructure modifications and its influence on microhardness, elastic modulus and tensile properties were investigated. Elastic modulus was decreased with increase in cooling rate from solutioning temperature. The samples solutionised at 900°C and quenched at sub-zero temperature contained α ″ martensite along with α′ and β phases and these lowered the elastic modulus. Among all the heat-treated samples, the one solutionised at 900°C and quenched at sub-zero exhibited lowest elastic modulus of 59 GPa and adequate tensile properties for the application as bioimplants.