Article révisé par les pairs
Résumé : Mechanical properties of metastable β-Ti alloys are highly dependent on the final microstructure, which is controlled by the thermomechanical processing. These alloys are used for biomedical applications and require a high mechanical strength as well as a low Young’s modulus to avoid stress shielding. Previous work on the development of cold swaged Ti-10Mo-20Nb alloy showed that the best compromise strength and Young’s modulus was obtained when the forming is followed by an aging heat treatment at 500 °C. In this work, Ti-10Mo-20Nb alloy was hot swaged and aged at 500 °C for 10 min, 4h and 24h. The microstructure was analyzed by X-ray diffraction, optical microscopy and transmission electron microscopy. Mechanical characterization was based on Vickers microhardness tests and Young’s modulus measurements. Aging at 500°C for 10 min after hot swaging resulted in a nearly 100% β phase microstructure while aging at 500°C for 4h or 24h led to a bimodal microstructure consisting on α precipitates dispersed in the β matrix. The higher hardness to Young’s modulus ratio was obtained for the sample aged at 500 °C for 4h. This value was higher than those obtained for the Ti-6Al-4V alloy and commercially pure Ti.

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