A novel method to fabricate reinforced Ti composites by infiltration of Al (Mg) into porous titanium

Abstract

We present a novel method to fabricate Ti composites with in-situ formed reinforcement. Porous Ti was prepared by a metal injection molding (MIM) process, and the pores in the Ti were filled with molten Al or Al-Mg. By a simple method of infiltrating the second and/or third elements for short times (30-120 s), we obtained reinforced Ti composites having near-net shape. In particular, we observed a notable feature that the addition of Mg to the molten Al considerably improves the mechanical properties of the Ti composites. From the microstructural and elemental analysis, we found that Mg plays an important role in the enhancement of mechanical properties by preventing the growth of the brittle TiAl3 phase and forming an Al(Mg) solid solution inside the pores.