Mean stress effect on crack propagation threshold at high stress ratios

The stress ratio effect on fatigue crack propagation threshold has been a subject of extensive investigation for decades in engineering materials. In the work, a modified mean stress correction model is proposed to predict long crack propagation threshold at high stress ratios as an extension of our previous work (Engineering Fracture Mechanics 2020, 223:106787). Moreover, the mean stress modified K-T diagram is derived based on the proposed model. Good accuracy can be achieved in terms of the experimental long fatigue crack propagation thresholds and K-T diagrams.