Influence of Heat Treatment on Microstructure and Mechanical Properties of Ti30Nb5Ta6Zr Alloy

A new beta-type alloy Ti30Nb5Ta6Zr for dental implant with low Young's modulus, medium-high tensile strength, good plasticity and biocompatibility was designed according to beta coefficient of stabilization k(beta) and d-electron theory. The change of microstructures and mechanical properties for the alloy after solution treatment followed by aging in beta phase region was investigated. It is found that the alloy is composed of metastable beta phase after solution treatment in beta phase region; omega phase precipitates when aged at low temperature, while a phase precipitates gradually when the aging temperature increases. With the aging temperature increasing, the strength and Young's modulus of the alloy increase first and then decrease, while the elongation of the alloy decreases first and then increases. The alloy after 800 degrees C, 30 min solution treatment and 500 degrees C, 12 h aging possesses excellent integrated mechanical properties and can meet the requirement for dental implant.