Towards a reliable determination of the intergranular corrosion rate of austenitic stainless steel in oxidizing media

Abstract : This paper studies the corrosion behaviour of non-sensitized stainless steels in oxidizing environments, where they can suffer intergranular corrosion. In this case, corrosion rate estimated by gravimetric measurement is not constant as a function of time. This paper proposes a quantitative modelling of the IGC kinetics. Two models were developed: the first one is based on the geometrical simulation of the groove penetration; the second one uses a semi-empirical approach based on the typical shape of the corrosion kinetics. Both models reproduce successfully the experimental corrosion kinetics observed for AISI 310L SS corroded in nitric acid containing oxidizing ions.