On the crevice corrosion behavior of nitrogen bearing austenitic stainless steels

The effect of nitrogen alloying in the crevice corrosion of SUS304 and SUS316 austenitic stainless steels was investigated by the determination of crevice corrosion initiation and repassivation potentials and by in-situ measurement of the dissolution behavior of corroding metal under crevice, via the moire method. The results showed that nitrogen alloying in austenitic stainless steels increased to more noble values both the critical potential for steady crevice corrosion, V C.CREV , and the critical potential for repassivation of crevice corrosion E R,CREV , Concerning the in-situ measurements, it was found that the dissolution just above the repassivation potential, V* II , decreased with nitrogen alloying for the SUS304 based alloys. In the alloys with molybdenum, it was not observed any significant effect.