Fabrication of reinforced α+β titanium alloys by infiltration of Al into porous Ti-V compacts

We present an efficient process to fabricate reinforced titanium α + β alloys. Porous Ti compacts containing vanadium were prepared by a metal injection molding process. Infiltration of molten Al and subsequent heat treatments were performed to synthesize a variety of Ti-V-Al alloys. The V-added specimens showed better mechanical properties than those of V-free Ti-Al intermetallic compounds. Microstructural observation of the fracture surface revealed that the lamellar structure in the Ti-V-Al alloys plays an important role in improving their mechanical properties by postponing the propagation of cracks. Notably, the lamellar structures in the Ti-V-Al alloys disappeared and the mechanical properties deteriorated as the Al infiltration duration time increased. Therefore, Al infiltration time is a crucial factor for successful growth of well-defined lamellar structured α + β phases in Ti-V-Al alloys.