Abstract
Using a slow strain rate technique, SSRT, with CCD camera system, initiation and growth behavior of intergranular stress corrosion cracking, IGSCC, for sensitized 304 stainless steel in aqueous solution containing various concentrations of NaF has been investigated. The largest decrease in maximum stress indicating the highest IGSCC susceptibility was found at 103 ppm NaF. And at the same concentration of 103 ppm NaF, the highest density of crack number and the shortest crack generation time was found. On the other hand, threshold stress intensity factor for IGSCC was independent of concentration of NaF. Crack growth rate showed a little dependence on NaF concentration, exhibiting a decrease at 103 ppm. It was obvious from the results that the highest IGSCC susceptibility at 103 ppm NaF was caused by increasing the number of cracks and decreasing the crack generation time, not by a change in threshold stress intensity factor for SCC or crack growth rate.
