Comparison of passivation behavior of SS316L with that of SS304 in tritiated water solution

摘要

Highlights ? Passivation of SS316L was not inhibited by tritiated water circumstance. ? Passive layer was thickened in tritiated water for both SS316L and SS304. ? SS316L is more compatible to tritiated water circumstance than SS304. Abstract The effects of tritium on the passivation behavior and passive layer formed in tritiated water circumstance for SS316L were investigated by means of an anodic polarization measurement technique and X-ray photoelectron spectroscopy, respectively. The results were compared with those for SS304, since it was predicted from a model of the tritium effects on corrosion suggested in the previous studies that SS316 would be less affective to tritiated water circumstance than SS304. As the results, the passivation inhibitory effect of tritium could not be observed for SS316L, while it was observed for SS304 and the other researched materials so far, as predicted. However, the thickness of the passive layer and the boundary between the passive layer and bulk of SS316L were found affected by tritium; thickened and gradated, respectively. From these results, it was concluded that SS316L would be more sustainable in tritiated water circumstance than SS304, although the corrosion of SS316L would be more or less enhanced in tritiated water circumstance.