Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10128634 | Materials Characterization | 2018 | 9 Pages |
Abstract
Metastable β Ti alloys based on Nb exhibit features that make them suitable for load-bearing biomedical applications, so it is crucial to evaluate their phase transformation and properties. This paper discusses the effects of aging heat treatments on the microstructure, phase transformation and mechanical behavior of Ti35Nb alloy. Samples were solution heat treated in the β field, quenched and aged under different conditions of heating rates, isothermal aging temperature and isothermal aging time. To enhance the alloy's mechanical behavior, thermal analysis and high temperature X-ray diffraction experiments coupled with Vickers hardness tests were employed to determine the temperature range of isothermal Ï phase precipitation, as well as α phase precipitation temperature, thereby providing information to optimize aging heat treatment conditions. Results indicate that Ti35Nb alloy subjected to a heating rate of 30â¯Â°C/min and an isothermal aging temperature of 500â¯Â°C applied for 4â¯h would ensure high mechanical strength and low elastic modulus. The application of these aging conditions led to a microstructure consisting of very refined α phase precipitates homogeneously dispersed in the β phase matrix, presenting an ultimate tensile strength of 972â¯MPa, elongation of 7.5% and elastic modulus of 78â¯GPa, making this aged alloy a promising candidate for biomedical applications. These results shed light on the correlations between phase transformations, microstructure and mechanical behavior in high solute content TiNb alloys for biomedical applications.
Related Topics
Physical Sciences and Engineering
Materials Science
Materials Science (General)
Authors
Mariana G. de Mello, Beatriz P. Dainese, Rubens Caram, Alessandra Cremasco,