Antero Pehkonen

The Use of Polarization Curves to Evaluate Stainless Steels in Highly Oxidizing Solutions

The corrosion behaviour of stainless steels in very oxidizing solution with redox-potential + 1200 mV vs. SCE was studied by corrosion potential and anodic polarization measurements. Some weight loss immersion tests were also carried out in order to verify the results of the electrochemical tests. Because the polarization curves and corrosion potentials for stainless steels give only a rough estimate of the corrosion behaviour, polarization curves and corrosion potentials were also measured for pure chromium, molybdenum, nickel and platinum as well as carbon steel in order to estimate the effect of alloying elements and the possibility of other chemical reactions in the transpassive region. It was found that this combination of measurements is a reliable method to evaluate the corrosion behaviour of stainless steels in dissolved ozone-containing solutions. .