1999 Volume 48 Issue 3 Pages 169-175
The effect of nitrogen alloying on the initiation, propagation and repassivation of crevice corrosion of SUS 304 and SUS 316 austenitic stainless steels was investigated through potentiostatic polarizations, cyclic polarizations and in-situ measurements of depth profiles by the moiré method. The results showed that nitrogen alloying in austenitic stainless steels increased to more noble values both the critical potential for steady crevice corrosion, VC, CREV, and the critical potential for repassivation of crevice corrosion EC, CREV. Concerning the in-situ measurements results, the dissolution rate just above the repassivation potential, VII*, decreased with nitrogen alloying for the SUS 304 alloys, and did not change in the SUS 316 alloys. The ratio of repassivating picture elements increased in both SUS 304 and SUS 316 with nitrogen alloying.