Effect of welding conditions on residual stress and stress intensity factor around remaining crack at seal welds

Abstract

In this study, the effects of seal welding conditions, such as welding heat input, crack depth, and plate thickness, on welding-induced residual stress and stress intensity factor (SIF) around the remaining crack were numerically investigated. It was clarified that the residual stress and the SIF at the downside crack tip is governed largely by the ratio of weld heat input to square root of crack depth, which was derived from welding thermal conduction theory as a representative of the temperature distribution along the crack. Furthermore the residual stress at the downside crack tip becomes compressive and the SIF becomes zero when the ratio is smaller than approximately 1.5.