Microstructural and mechanical characterization of biomedical Ti-Nb-Zr(-Ta) alloys

In recent years there has been a significant development of novel implant alloys based on beta-Ti such as Ti-Nb-Zr and Ti-Nb-Zr-Ta alloys systems. The purpose of this work is to provide characterization of Ti-35.3Nb-5.1Ta-7.1Zr and Ti-41.lNb-7.1Zr alloys, in which Nb will substitute the atomic amount of Ta, with emphasis in the property-microstructure-composition relationships. These alloys are produced from commercially pure materials (Ti, Nb, Zr and Ta) by an arc melting method. All ingots were submitted to sequences of heat treatment (1000 degrees C/2 h - WQ), cold working by swaging procedures and other heat treatment (1000 degrees C/2 h - WQ). Specimens, in as cast and heat-treated condition, were examined by light and scanning electron microscopy (SEM). These results suggested the presence of beta- and omega-phases. Mechanical properties were based on tensile and hardness tests. These alloys exhibit a lower modulus than that of conventional Ti alloys and the other mechanical properties are suitable for biomedical applications. (c) 2006 Elsevier B.V. All rights reserved.