Intergranular corrosion in sensitized austenitic stainless steel subjected to tensile loading and unloading in the elastic-plastic region.

This study investigates the influence of mechanical conditions on intergranular corrosion (IGC) in type 304 austenitic stainless steel. Electrochemical potentiokinetic reactivation and oxalic acid etching tests were conducted on specimens under tensile loading and unloading in the elastic-plastic region. The results show that their IGC susceptibility became higher than that of intact specimens. Furthermore, tensile loading during corrosion led to an increase in the IGC susceptibility of plastically deformed specimens. The IGC susceptibility of high-energy grain boundaries (GBs) was increased by elastic and plastic deformation around the GBs. Low-energy GBs exhibited little IGC susceptibility for all mechanical conditions. • Intergranular corrosion tests were done on austenitic stainless steel under tension. • Reactivation rate increased as the mechanical conditions became more severe. • Low-energy grain boundaries have high intergranular corrosion resistance. • Tension raises intergranular corrosion susceptibility of high-energy grain boundaries. [ABSTRACT FROM AUTHOR]