Аннотация:The paper reports the theoretical and experimental bases of the CDCP (Coulometric detection of corrosion products) method and examples of its application for the quantitative determination of the ionic forms of corrosion products of carbon steel, including the heat-affected corrosion areas of welding seams under strain ageing (ACWS). The experiment technique that we developed allowed us to perform selective determination of corrosion products (e.g., Fe+2 and Fe+3 in a single experiment) in the range of 1–5 μg with standard deviation sr = 0.05.