Creep-fatigue crack growth in power-plant materials and components

The stress-time-temperature history experienced by header, turbine casings, turbine rotors and pipes in conventional power-plants necessitate the consideration of creep deformation and damage in design and remaining life prediction. In this paper, some of the recent developments in predicting crack growth behavior under creep-fatigue conditions using the concepts of time-dependent fracture mechanics are reviewed. While substantial progress has been made in this field, several gaps in the technology still exist. The paper concludes with a description of the limitations of this approach and where future research must be focussed.