Crack Growth Resistance Characteristics Determination Algorithm for Creep-fatigue Interaction

For the experimental crack paths in tested specimens the governing parameter for the 3D-fields of the stresses and strains at the crack tip in the form of In-integral was calculated by finite element analysis along crack front. The governing parameter of the stress-strain fields in form of In-integral was used as the foundation of the creep stress intensity factor. The creep stress intensity factor approach was applied to the fatigue crack growth. The numerical and experimental results demonstrated that Kcr is the most effective crack tip parameter in correlating the creep-fatigue crack growth rates in power plant materials and can be used reliably for practical purposes.