Pitting corrosion ( eng. Pitting , from eng. Pit - to cover (s) pits) - corrosion of metals , leading to the formation of pitting, that is, ulcers, cavities in the metal starting from its surface. Externally, pitting is manifested in the form of the appearance of recesses on the surface of the metal. Pitting occurs mainly in the protective layer (deposited or formed naturally) at the places of various defects (cracks from internal stresses, pores, microinclusions, grain boundaries coming out to the surface, dislocations, etc.). Rolling mill scale or its residues on steel surfaces is one of the causes of ulcerative corrosion. Pitting corrosion is observed in solutions of ferric chloride, a mixture of hydrochloric and nitric acids , sea water and many other aggressive environments. Destruction is observed in the presence of corrosive process ions (Cl, Br, I) and passivators in the corrosive medium.
Links
- Pit Happens - Copper Corrosion in Household Plumbing. (eng.)
- Pitting corrosion
- Pitting Corrosion - Corrosion Doctors [1]
- Pitting Corrosion Pitting Corrosion Theory (English)
- Chemical explanation of pitting corrosion - University of Rhode Island, College of Engineering [2]
- Guidelines for the training of inspectors on visual and measuring quality control of paint work ”/ Ch. ed. Pirogov V.D .. - Yekaterinburg: Publishing House "Origami", 2009. - 202 p. - ISBN 978-5-9901098-1-5 .