In-situ reaction mechanism of Ti3AlC2/TiAl3 composite prepared by powder metallurgy

The layered MAX phase Ti 3 AlC 2 is an excellent reinforcement for TiAl 3 matrix. However, unraveling the complex in-situ reaction mechanism of Ti 3 AlC 2 /TiAl 3 composites is a challenge of great scientific and practical significance. In this paper, Ti 3 AlC 2 /TiAl 3 composites were sintered at different temperatures from 630 to 1300 °C by using the TiH 2 , Al and TiC powder as starting materials via powder metallurgy route. Then the samples were characterized using multiple advanced analytical tools to systematically investigate the in-situ reaction mechanism of the Ti 3 AlC 2 /TiAl 3 composites. The results indicate that the reinforcement Ti 3 AlC 2 begins to generate at 1100 °C, and a coherent interface relationship is formed between the basal plane of hexagonal Ti 3 AlC 2 phase and TiAl 3 matrix. Moreover, this coherent relationship can be inherited into the final Ti 3 AlC 2 /TiAl 3 composites, which is more conducive to the enhancement of interfacial bonding as well as better transfer of stresses, thus effectively improving the strength and toughness of the composite.