Crevice corrosion definition

Pitting may be defined as a limiting case of localised attack in which only small areas of the metal surface are attacked whilst the remainder is largely unaffected, and this definition is applicable irrespective of the mechanism involved dezincification, crevice corrosion and impingement attack can all result in pitting, although the mechanisms of these three processes are quite different. 

These techniques for evaluating crevice corrosion resistance involve holding (static) or incrementally changing (step or scan) the potential or current. Some of the more frequently used techniques for evaluating crevice corrosion resistance are listed below, following the definitions given in ASTM G 15 ... 

To measure the repassivation potential, severe crevice corrosion must be initiated on a creviced specimen and allowed to propagate for a fixed period of time or, more usually, to a definite amount of anodic charge. Then the potential is... 

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