Pitting Damage Growth Behavior near the Weld Seam of 304 Stainless Steel

The 304 stainless steel pipeline welding process was simulated in Simufact Welding software, and the residual stress distribution on the outer surface near the weld was obtained. In the ABAQUS software, the stress concentration in a single pit was analyzed, and the relationship between the stress concentration factor and the shape of the pit was also analyzed, and the change rule of pitting corrosion rate and pitting pit shape under stress was put forward. The results showed that the corrosion tendency and corrosion rate of the sample increased under the action of stress. Affected by stress, pits usually corroded faster in the direction perpendicular to the principal stress, and gradually formed flat pitting pits perpendicular to the principal stress or even developed into cracks. The stress must reach a certain value to have a significant effect on corrosion. For 304 stainless steel hemispherical pitting damage, a residual stress of 100 MPa might have a significant impact on the development of pitting damage.