Produção, processamento e caracterização de ligas do sistema Ti-Nb-Mo-Zr com baixo módulo de elasticidade para aplicações biomédicas

Abstract

Metastable β titanium alloys have been developed for biomedical applications due to their low elastic moduli and functional properties which can be adjusted to different parts of an orthopedic implant through thermomechanical processing and chemical composition control. This study aimed to produce, process and characterize experimental titanium alloys belonging to the Ti-Nb-Mo-Zr system for biomedical applications, as well as an industrial scale alloy to be used in the manufacture of orthopedic implants. The experimental alloys were obtained via arc melting followed by homogenization heat treatment, while the Ti-23.6Nb-5.1Mo-6.7Zr alloy was produced by vacuum arc remelting (VAR), thermomechanically processed under different conditions and aged. Both samples were characterized by X-ray diffractometry, optical and scanning electron microscopy, elastic moduli measurements and Vickers microhardness tests. Among the different processing conditions, the Ti-23.6Nb-5.1Mo-6.7Zr alloy annealed at 950 ° C for 1 h, after 90 % of cold rolling, with a β single-phase microstructure composed of grains refined, was the one that presented the highest hardness / elastic modulus ratio.