At present, the hot-section components in high temperature engineering applications like gas turbine engines are primarily made from actively cooled age hardened nickel alloys known as super-alloys DeBarbadillo(1988), Sims(1991), and DiCarlo(1989). Currently there is a drive in the turbine industry to increase inlet temperatures, to reduce material densities, and to eliminate component cooling Sims(1991). One class of materials with the necessary high temperature properties and low density desired is engineering ceramics. Monolithic ceramics, however, suffer from two major reliability issues. These are sensitivity to processing and low fracture toughness. This last item, leads to catastrophic failure and severely restricts ceramics from use in aerospace or land based turbine engine applications DiCarlo (1989). To overcome this problem, the continuous fiber reinforced ceramic composite (CFCC) was developed.

The goal of this effort is to characterize the damage processes associated with a candidate CFCC material with reference to how these processes modify the stress state and the material state of the ceramic composite system, to incorporate and combine these issues into a damage mechanics methodology, and to apply this methodology to the assessment of damage and life prediction for the candidate material system.