Age-hardening of Ti-35Nb-7Zr-5Ta alloy for orthopaedic implants

Abstract

Bone injuries and failures often require the inception of implant biomaterial. Research in this field has received increasing attention recently. In particular, porous metals are attractive due to its unique physical, mechanical, and new bone tissue ingrowth properties. The aim of this work is to investigate age hardening behavior of Ti-35Nb-7Zr-5Ta alloy produced by powder metallurgy. Samples of Ti-35Nb-7Zr-5Ta were produced from a mixture of hydrided powders followed by uniaxial and cold isostatic pressing with subsequent densification by sintering at 1500 °C, in vacuum. After that, the samples were heat treated in three steps; solution treatment (1100/°C), air cooling and aging (600 °C for 4 and 6 hours). Sintered samples were characterized for microstructure and microhardness by scanning electron microscopy and Vickers indentation, respectively. In the homogenized condition alloy exhibited a microstructure consisting primarily of a beta Ti matrix with grain boundary alpha precipitates and a low volume fraction of primary alpha precipitates. In the ageing condition the alloy exhibited the precipitation of refined scale secondary alpha precipitates distributed homogeneously in the beta matrix

New Ti–35Nb–7Zr–5Ta Alloy Manufacturing by Electron Beam Melting for Medical Application Followed by High Current Pulsed Electron Beam Treatment

“…EBM-manufactured TNZT alloy also shows a preferred [001] β crystallographic orientation along the growth direction during the fabrication. It is well known that the β phase of Ti provides lower elastic modulus than the α phase, due to this the β-Ti alloys may fill most of the imposed demands for an ideal biocompatible alloy for bone substitution [40].…”

Desenvolvimento de filmes de TiO2 produzidos por tratamento eletroquímico sobre a liga Ti6Al4V: sua caracterização físico-química e mecânica

“…Alguns estudos mostram que uma forma de abaixar mais o módulo de elasticidade nas ligas de Ti é através da adição de nióbio e tântalo. Com esses elementos pode-se conseguir um módulo E ≈ 55 GPa [9][10][11].…”