STRESS-CORROSION CRACKING OF SENSITIZED TYPE-304 STAINLESS-STEEL IN SULFATE AND CHLORIDE SOLUTIONS AT 250-DEGREES-C AND 100-DEGREES-C

Slow strain rate tests have been used to study the stress corrosion susceptibility in 0. 01M Na//2SO//4 and 0. 01M NaCl as a function of applied potential at 250 and 100 C. At 250 C, intergranular cracking occurs at potentials greater than a critical potential, minus 0. 3 V//H, which is independent of the anion, but decreases with increasing degree of sensitization. At potentials higher than 0. 0 V//H, simultaneous transgranular and intergranular crack initiation occurs in chloride. The potential at which transgranular cracking appears coincides with the potential at which quench-annealed material is susceptible to transgranular cracking. At 100 C, intergranular cracking initiated on pits occurs only at potentials greater than the pitting potential.