2. Corrosion

Corrosion is the result of a chemical or electrochemical reaction between the heat transfer surface and the flowing fluid. Initially, the term corrosion was used for the process of degradation of metallic materials by an aggressive medium. It was later extended to include the degradation of non-metallic materials by an aggressive medium. In specialized literature, the notion of corrosion is often evoked by the term chemical or physico-chemical resistance.