High-temperature oxidation behavior of ceramic particles-reinforced TiAl composites with multilayered structure

To investigate the effect of different reinforcements on high-temperature oxidation resistance of TiAl alloys, ceramic particles-reinforced (graphene oxide (GO), SiC, BN) TiAl composites with a multilayered structure were prepared by spark plasma sintering (SPS) using high throughput concept. The TiAl composite was fully lamellar structure, including GO, SiC and BN reinforcements each layer respectively. The effect of different reinforcements on oxidation layer of TiAl composites was observed directly after cyclic oxidation testing at 950 °C. The mass gain of TiAl composites was 2.09 mg/cm2 lower than that of 2.81 mg/cm2 for TiAl alloy oxidized 100 h, corresponding to a lower oxidation rate. The oxidation layer of TiAl composites was composed of TiO2 and Al2O3, and presented a multi-layer structure. The results showed that SiC and GO reinforcements improved the high-temperature oxidation resistance of TiAl alloy, while BN reinforcement played a negative role. The effect of different reinforcements on oxidation mechanism of TiAl alloys was mainly attributed to the ceramic particles-inhibited oxygen diffusion and ceramic particles-indued the nitridation susceptibility.