Crevice corrosion cautions

The above considerations show that although considerable advances have been made in developing laboratory controlled potential tests for evaluating crevice corrosion and pitting, the results must be interpreted with caution. 

Using EN techniques, it has been claimed that it is possible to detect the onset of corrosion, determine whether it is uniform or localized, and even distinguish between pitting and crevice corrosion [729]. There is evidence, however, that this claim should be taken with some caution [722]. At its present state of development the most common use for the EN technique has been in corrosion monitoring [724]. Although EN shows great promise for use in monitoring of MIC, there have been few applications to date. 

Stainless steels are unpredictable in sea water. In some circumstances, certain grades have stood up well but in other cases rapid attack has occurred. Stainless steels are prone to stress-corrosion cracking and susceptible to attack due to crevices and deposits. The consensus seem to be that stainless steels may be excellent in certain cases but must be used with caution. 

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