Stress corrosion cracking of sensitized type 304 stainless steel in borate solutions at elevated temperatures

The SCC susceptibility of furnace sensitized Type 304 stainless steel was studied using slow strain rate tests in 0.01m B(OH)s + 0.001m LiOH solution as a function of applied potential at temperatures ranging from 125 to 275lt. slashC. A potential-temperature plot in which domains of IGSCC and ductile failure are delineated by a temperature dependent critical potential for IGSCC has been determined. No cracking was observed at 125lt. slashC, but the potential range for cracking increases with increasing temperature. Results of the tests carried out under applied potential were compared with those conducted in air saturated solutions under open circuit conditions. Since the results in both types of tests were equivalent, it was concluded that the electrode potential is the main factor in determining the susceptibility to IGSCC