High-temperature oxidation behaviour of Ti3Si(1−x)Al x C2 in air

The oxidation behaviours of bulk Ti3Si(1−x)AlxC2 prepared by hot pressing were investigated. The results showed that the isothermal oxidation behaviour of Ti3SiC2 obeyed a parabolic law between 900 and 1100°C, and followed a two-step parabolic rate law between 1200°C and 1300°C. The cyclic oxidation behaviour of material is assumed to obey a three-step parabolic rate law at 1100°C and 1200°C. The calculated activation energy of isothermal oxidation is 101·43 kJ·mol−1. The oxide layers consisted of a mass of α-Al2O3 and little TiO2 and SiO2 are observed on Ti3SiC2 as a dense and adhesive protect scale. The oxidation mechanism varies with the additive aluminum that greatly improves the oxidation resistance of Ti3SiC2.