ANTI‐CORROSION METHODS AND MATERIALS: 3: Forms of corrosion Part 2: Pitting corrosion, interangular attack and selective leaching Available to Purchase

Pitting Pitting is possibly the most expensive form of corrosion, in that one small hole can result in the failure or destruction of a process or plant. By its very nature it is a localised form of attack, the diameter of the resultant pit being approximately the same as its depth. Some materials are very prone to pitting—the pits are so close that the surface resembles a roughened specimen. The most important factor, that of pit depth, is sometimes referred to in terms of ‘pitting factor’. This relates the ratio of deepest pit to average metal penetration, the latter being derived from the weight loss of the specimen. Uniform corrosion has a pitting factor of unity.