Thickness and weld orientation effects on fatigue crack growth after a single tensile overload

Numerical calculations were performed to investigate the effects of thickness and weld orientation on welding residual stress (WRS) and fatigue life after a single tensile overload (OL) using a centrally-cracked steel specimen. First, welding simulations were carried out to predict WRS due to the change in thickness and weld orientation. The WRS was then considered in elastic-plastic crack growth calculations in addition to the single tensile OL. A rigorous discussion was conducted to explain the effects of thickness and weld orientation on the state of the local stress ahead of the crack tip, crack driving force, and fatigue life.