Influence of Oxygen Concentration on the Initiation of Dissolution Corrosion on 316L Austenitic Stainless Steel at 450°C

Abstract

This work presents first results of the study on the influence of the LBE oxygen concentration on the initiation of dissolution corrosion in 316L austenitic stainless steels. 316L steel specimens were exposed at 450 °C to static liquid LBE with controlled and constant oxygen concentration of 10−5, 10−6 and 10−7 mass% for 1000 hours. Corroded specimens were analysed by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Limited oxidation corrosion and no dissolution corrosion was observed in the specimens exposed to LBE containing 10−5 and 10−6 mass% oxygen, while dissolution corrosion with a maximum depth of 59 μm was found in the specimen exposed to LBE containing 10−7 mass% oxygen.