Crevice corrosion of 304 L- and 316 L-stainless steels has been examined for 7.2 or 1.8Ms in nitric acid solutions with/without RuNO (NO
3)
3, by measuring the mass loss of the specimen, the amounts of metal ions dissolved, and the galvanic current.
Specimen surface at/around the crevice corroded more vigorously than that without the crevice, and the tendencies became more remarkable at higher HNO
3 concentrations, higher temperatures, and with RuNO (NO
3)
3. Current flowed from the specimen with crevice to the specimen without crevice through a lead wire, when these connected specimens were immersed in a HNO
3 solution containing RuNO (NO
3)
3. The susceptibility to the crevice corrosion was higher on 316L than on 304L stainless steel.
A mechanism on the crevice corrosion of stainless steels in HNO
3 solutions is discussed in terms of a catalytic action of Fe
3+ ions accumulated on the surface at the crevice.
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