Diagnosis of quality of fresh water for carbon steel corrosion by Mahalanobis distance

Corrosion diagnosis of carbon steel in fresh water was carried out by electrochemical method and Mahalanobis-Taguchi (MT) method. The corrosion morphology of carbon steel was classified by the combination of i–E curve measurement and chronopotentiometry. The MT method is one of discriminant analysis and can diagnose distinction data by multiple causes, i.e., ion concentrations. In the present paper, the concept for the application of this method to corrosion diagnosis is introduced. Additionally, electrochemical method was used for specific classification of carbon steel corrosion. By comparing the results of electrochemical measurements with those of Mahalanobis distance, the utility of MT method in the corrosion diagnosis was discussed.