Regularities of the Influence of Substitutional and Interstitial Alloying Elements on the Corrosion Properties of Austenitic Stainless Steels

Pitting corrosion studies were carried out on nitrogen containing austenitic stainless steels of different compositions and concentrations of alloying elements. As was shown there is a certain predicted influence of the concentration of each alloying elements as chromium, manganese, nickel, carbon and nitrogen on the pitting potential (Eb) of investigated steels with the nitrogen content less than 0.169 wt. %. However with an increase of the nitrogen content to a certain value (in our study up to 0.82 wt. %) the predicting of alloying elements influence on pitting potential of the steels requires a new approach. Based on the analysis of the experimental results and to take into account the influence of all alloying elements in steel on the pitting potential, a regression equation is proposed. In the presence of nitrogen, the positive role of carbon on the pitting resistance of stainless steel was shown, and the critical values of the total content (C + N) and the C / N ratio were determined, allowing prediction of the best composition of stainless steel.