MECHANICAL SURFACE-TREATMENT EFFECTS ON THE INTERGRANULAR STRESS-CORROSION CRACKING SUSCEPTIBILITY OF SENSITIZED 304-STAINLESS STEEL IN HIGH-TEMPERATURE WATER

Surface treatment effects on IGSCC susceptibility in 561 K pure water were investigated with respect to machining, grinding and shot peening. Susceptibility was increased by machining and grinding when tension above 300 MPa was produced on the worked surface. When surface roughness was below about 20 mu m and residual compression was above approximately 500 MPa, shot peening suppressed initiation of IGSCC in the SCC test up to an applied stress of 2. 00 sigma //y.