SOUSA, Flávio Vieira Vasques de ; MURI, P. ; ASSIS, K.S. ; ROCHA, A.C. ; Isabel C.P. Margarit-Mattos ; MATTOS, Oscar Rosa
Resumo: There is great industrial interest in developing non-destructive tests for the detection of deleterious phases in stainless steels. In this context, the Electrochemical Potentiodynamic Reactivation (EPR) technique, described by the standard ISO 12732, can be used as a tool for quantitative analysis of the degree of sensitization of austenitic stainless steels. Experimental parameters that influence directly the test results are not dealt with carefully in the literature. This study then performs a critical analysis of the standard usefulness, mainly evaluating the influence of potential scan rate and concentration of potassium thiocyanate (KSCN) in the test solution. Actually, the EPR method can be sensitive to the degree of sensitization of the studied material. However, the classification given by ISO 12732 can lead to errors whether standard curves previously established for the steel are not considered.
