316L stainless milling behaving mechanism in enamel coatings: A strategy for mechanical and corrosion improvement

Abstract

To achieve corrosion resistance and mechanical robustness properties simultaneously, 316L stainless steel powder was employed as mill additives in SiO₂–B₂O₃–Na₂O–SrO slurry system enamel coating. The sintering process, gases consuming, microstructure, interface adhesion, and corrosion mechanism of the prepared enamel coatings were investigated. The results indicated that during sintering, 316L powder reduced coatings porosity by forming internal carbides through the Cr-poor reaction of carbon-containing gases adsorption in the pores due to its low-carbon activity. Additionally, the powder partially dissolved into the enamel coating matrix, contributing to a significant enhancement in the coating's mechanical properties through its own ductility and toughness. Moreover, the peeling of the gel layer from the enamel coating surface was slowed in acidic environments, thereby enhancing the enamel coatings' long-term resistance to acid corrosion.