Prediction of component failure at high temperature such as in gas turbine engines and rocket engines is an extremely complex issue because of the combined effects of creep, plasticity and strength, and modulus degradation with time and temperature. The prediction becomes even more complex when cyclic loads are encountered and when the state of stress is multiaxial and non-proportional. The research program addresses this important class of problems through the use of state variable cyclic viscoplasticity theory to model the behavior of the material under isothermal conditions.
