The effect of cold-rolling on the microstructure and corrosion behaviour of 316L alloy in FLiNaK molten salt

The effect of cold-rolling on the microstructure and molten salt corrosion behaviour of 316L alloy was investigated. Corrosion tests were performed in FLiNaK salt at 600 °C for 300 h. The present results indicate that cold-rolling leads to enhanced corrosion in molten salt despite its beneficial effect on the alloys mechanical properties. It is shown that the corrosion resistance of cold-rolled 316L alloy is largely governed by the presence of high-angle grain boundaries (HAGBs) and geometrically-necessary dislocations (GNDs). Exacerbated corrosion is thus directly related to the increased prevalence of grain boundaries and dislocations within the microstructure.