Mechanical behavior and microstructure control of the low-cost titanium-oxygen alloy prepared by ball milling and spark plasma sintering

Abstract Element substitution by light, economic, and innoxious components has been a promising strategy to improve the mechanical performances of Ti alloys. In this study, we develop a novel Ti-O alloy using ball milling (BM) and spark plasma sintering, which exhibits an excellent yield strength, 150% higher than that of commercially pure titanium and similar to that of the commercial Ti-6Al-4V alloy. In addition, the microstructure of the Ti-O alloy can be controlled by simply tuning the ball-to-powder ratio in the BM. An optimization is carried out, leading to a uniform distribution of the crystalline grains and refined grain size. Consequently, both yield strength and ductility can be enhanced. This study not only reveals the mechanism of microstructure refinement and homogenization in titanium alloys by the BM, but also provides a feasible strategy for the advancement of high-performance titanium alloys.