Temperature and potential dependence of crevice corrosion of AISI 316 stainless steel

Crevice corrosion of AISI 316 steel has been investigated in a modified 'Avesta Cell'. Potentiodynamic scans have been made in sodium chloride solutions of various pH values at different temperatures with and without crevice. The breakthrough potential changes discontinuously with temperature. At all temperatures the attack is localised to the crevice, and the breakthrough potential is lower than for experiments without the crevice. The experiments in acidified environments indicate that crevice corrosion at low temperatures results from acidification in the crevice. At higher temperatures crevice corrosion is believed to be the result of metastable pitting stabilised by the crevice. (C) 2001 Elsevier Science Ltd. All rights reserved.