Oxidation behaviour of Ti 3SiC 2-based ceramic at 900–1300°C in air

Abstract

The isothermal oxidation behaviour of Ti 3SiC 2-based ceramic containing 7 wt.% TiC at 900–1300°C in air has been investigated. The growth of the oxide scales on Ti 3SiC 2 from 900°C to 1100°C obeyed a parabolic law, whereas at 1200°C and 1300°C, it was a two-step parabolic oxidation process. The scale was composed of an outer layer of coarse-grained TiO 2 (rutile), an inner layer of a mixture of fine-grained TiO 2 and SiO 2 (tridymite). Furthermore, the oxide scale at 1100°C contained a discontinuous SiO 2 “barrier” sandwiched in the outer TiO 2 layer. The scales formed on Ti 3SiC 2 were dense, adhesive and have good adhesion with the substrate during the cyclic oxidation.