Formation of Ti-Matrix Composites for Lightweight Structural Components by Mechanical Alloying and Subsequent Annealing

Abstract

In this work, a lightweight Ti-10Mg-5Al (wt. %) alloy for structural components was produced by mechanical alloying. A metastable α-Ti(Al,Mg) solid solution was obtained after 50h of milling. Diffraction peaks ascribed to the Mg phase were detected in the XRD pattern of the sample heat treated at 600°C. This phase tends to oxidize with the increase of temperature giving rise to MgO. The structure of the mechanically alloyed and 900°C heat treated sample consisted of a Ti(Al) solid solution with dispersed MgO particles in the matrix. Hardness and Young’s modulus values obtained from ultramicrohardness tests confirm the strength improvement of the Ti-based alloy due to the MgO reinforcement.