Residual stress effects on fatigue crack growth rate of mild steel S355 exposed to air and seawater environments

In this paper, the parameters of fatigue crack growth rate for Q355J2 steel exposed to air and seawater were presented using the “Paris' law” based on the stress intensity factor (SIF), J-integral, crack tip opening displacement (CTOD) and crack tip opening angle (CTOA). The residual stress of a compact tension specimen is analysed by modelling of the welding process based on subsequently thermal mechanical stress analysis. Effect of the residual stresses on the fatigue crack growth rate is investigated by considering the numerically predicted residual stress distribution due to welding. The fatigue crack growth rate based on the parent material considering residual stress effects is compared with welds and the heat affected zone (HAZ).