MODELS FOR CREEP CRACK GROWTH IN STEADY STATE AND TRANSIENT STRESS FIELDS.
Abstract
A generalized model for steady-state creep crack growth is presented, in which the development of the steady-state stress field ahead of a crack, and the growth of cavities in that stress field, are treated as separable problems. Results of some recent computer simulations, in which the affect of relaxing several of the assumptions used by this model, have been studied. The analytical model is found to be reasonably accurate. Next, the growth of cracks in a transient stress field is discussed. Finite element analysis has led to a time-dependent crack tip parameter. This can be used to develop models for crack growth.