Microstructure Evolution of in situ (Ti3AlC + Ti5Si3)/Ti3Al Composite Sheet with a Novel Quasi-continuous Chain Reinforcement Distribution Architecture Prepared by Using Roll Bonding and Reaction Annealing

The Ti3Al matrix composite sheet with a novel quasi-continuous chain reinforcement distribution was prepared by using roll bonding and subsequent reaction annealing with pure Ti and SiCp/Al foils. The (Ti3AlC + Ti5Si3) reinforcements were produced by in situ reaction of the as-rolled Ti–(SiCp/Al) laminated composite sheet after a two-stage annealing treatment including first annealing at 660 °C and second annealing at 1250 °C. The microstructure evolution during the reaction annealing was investigated. In the first reaction annealing, TiAl3 was formed, and the SiC particles were pushed together due to the Kirkendall effect, and after the second reaction annealing, Ti3Al, Ti3AlC and Ti5Si3 were synthesized. In addition, the reinforcement distribution presents a quasi-continuous chain microstructure in Ti3Al matrix composite sheet.