PREDICTION OF TRANSIENT CREEP RESPONSE UNDER COMBINED PRIMARY AND SECONDARY LOADING

Residual stress effects on creep deformation and fracture play a significant role in structural integrity assessments of engineering components. The focus of the current work is to investigate creep behaviour of mechanically loaded cracked structures in the presence of residual stress fields. Finite-element analyses have been carried out on single edge notch bend, SEN(B), and tension, SEN(T), specimens at different residual stress and mechanical stress levels. The redistribution time and associated stress relaxation for combined primary and secondary (residual) stresses have been determined (from the finite-element analysis) and interpreted using the transient fracture mechanics parameter, C(t). The observed trends are consistent with earlier studies involving combined thermal and mechanical stress.