The microstructure and tensile properties of the Ti2AlC reinforced TiAl composites fabricated by powder metallurgy

The TiAl matrix composites reinforced with Ti2AlC particles have been successfully fabricated utilizing the method of hot press consolidation followed by isothermal forging. Microstructures and tensile properties of as-sintered and as-forged conditions were investigated. The results show that the as-sintered composites consist of γ-TiAl, α2-Ti3Al and Ti2AlC phases. Microstructure analysis indicates that the products exhibit inhomogeneous microstructure and the Ti2AlC particles tend to disperse on the grain boundaries. A fine-grain and homogenous microstructure was obtained through isothermal forging. The tensile property of as-forged composites was improved simultaneously, with elongation (δ) increasing from 12.10% to 30.87%. In particular, at 1000 °C, the engineering strain was up to 176%, exhibiting superplasticity.