Effect of Some Environmental and Stainle

The double loop-electrochemical potentiokinetic reactivation (DL-EPR) method estimates the degree of sensitization in stainless steels through the ratio of peak current densities during reactivation and activation scans. This study aimed to assess how additional metallurgical variables, like inclusion content and cold work, as well as environmental conditions such as solution deaeration and aging, impact this ratio in austenitic stainless steel Types AISI 304 and AISI 303. Testing revealed that the presence of inclusions in AISI 303, which has higher sulfur content compared to AISI 304, led to an increase in the degree of sensitization. Conversely, cold work was found to decrease this sensitization in AISI 304. Notably, the DL-EPR test was effective in distinguishing between solubilized and thermally aged specimens, with confidence intervals indicating non-overlapping results. The study also confirmed that the testing solution composition (0.5 mol/L H2SO4 and 0.01 mol/L KSCN) and deaeration conditions did not significantly affect the results obtained. This suggests potential flexibility in the application of the DL-EPR technique, particularly in field settings where pre-prepared aerated solutions could be utilized.