Harmonic structure design of Ti-6Al-4V alloy by High-pressure gas milling process

AbstractTi-6Al-4V alloy has been widely used for biomedical and aerospace applications, due to the excellent combination of mechanical and chemical properties. In this study, a new heterogeneous bimodal microstructure design, termed as harmonic structure design, consisted of coarse-grained area (Core) enclosed in a three-dimensional continuously connected network of fine-grained structure (Shell), is proposed for the strengthening of Ti-6Al-4V alloy to achieve improved performance of components. A novel high-pressure gas milling process, called jet milling, followed by spark plasma sintering has been proposed to create bimodal harmonic structure. The sintered Ti-6Al-4V alloy compacts with harmonic structure exhibited a significantly better combination of strength and toughness, as compared to their homogeneous fine- and coarse-grained counterparts.