2020 Volume 69 Issue 11 Pages 315-322
We often experienced that crevice corrosion behavior on initiation and propagation changed among the tests if the test condition were the same in the crevice corrosion test. This paper makes clear the variation of the initiation site properties: position, number, time orders and initiation time, and the propagation behavior of the crevice corrosion after 600 s from the initiation among 16 times tests. The crevice corrosion tests of SUS304 stainless steel were carried out on the same test condition for 16 times in artificial seawater under the constant potential of 499 mV (SHE). We confirmed that the initiation site properties were very different in the test chances. The first initiation of crevice corrosion tends to occur at the near site of crevice mouth. The second initiation site was not influenced by the position of the first initiation. The crevice corrosion initiation time near the crevice mouth tends to be shorter than that occurred in the inner part of crevice. It was not influenced by the order of initiation. The crevice corrosion areas after 600 s from the first initiation time were changed from 0.015 to 0.110 cm2. The propagation rate of crevice corrosion area was influenced by the potential distribution that was depended on the IR drop from the crevice mouth. The propagation rate of the crevice corrosion near the crevice mouth tended to be faster than that occurred in the inner part of crevice.