Durability Modeling of Fiber Reinforced Ceramic Matrix Composites

High temperature fiber reinforced ceramic matrix composites (CMC's) show much promise for application in current and future generation aeropropulsion systems. These materials systems possess a combination of properties: light-weight, high strength, high temperature capability, and non-brittle failure mode; not possible with any other class of material. However, the turbine hot section is a very harsh environment and current development work has shown that these materials may suffer for environmental degradation during service. The successful application of these materials in man- rated engines requires that the factors contributing to material degradation be recognized, and accounted for. The many possible material combinations and application-specific thermo-mechanical-environmental service conditions renders the development of a purely empirical approach extremely time-consuming and expensive. An alternative approach is to develop some form of mathematical model able to predict material durability based on a knowledge of the material constituents and the general operating conditions (time, temperature, load, etc.). The opportunity presented by this proposal is to demonstrate a micro-mechanics approach to durability modeling to allow the prediction of composite mechanical performance as a function of time, temperature and mechanical loading condition.