Ceramics and Composite Materials

Ceramic matrix composites (CMC) have received significant attention from many researchers for being excellent candidates for gas turbine applications. Using CMCs led to a significant improvement in fuel consumption and thrust to weight ratio in comparison to metal based alloys. In addition, the low density of CMCs allows potential weight savings of up to 30% comparing to Ni-based super alloys. Si-based ceramics have excellent oxidation resistance due to the formation of a protective silica layer when it reacts with dry air, however their oxidation behaviour is not fully understood. Oxidation behaviour of silicon melt infiltrated SiC/SiC ceramic matrix composites (CMC) was studied in air up to 1400°C for 1, 5, 24 and 48 h in a furnace. Weight gain and oxide layer thickness measurements were performed to study the oxidation kinetics and how the oxidation temperature and time affect the oxidation kinetics of SiC/SiC composites. Different characterisation techniques were used to study the formation and the

nature of oxide layer (SiO2).