Corrosion Behavior of NC-304 Stainless Steel Subjected to SMAT in H2SO4 Solution

304 stainless steel was subjected to surface mechanical attrition treatment (SMAT) and the average grain size of the as-treated surface was about 20 nm.Weight loss tests and electrochemical measurements were used to compare the corrosion behavior of coarse-grained (CG) and nano-crystallized (NC) 304 SS in 5% (mass/%) H2SO4 at 80 ℃ and room temperature (RT).TEM and SEM were used to analyze the relationship between the microstructure and corrosion properties.Weight loss test suggests that NC-304 SS obviously deteriorated after surface nano-crystallization and main corrosive feature was inter granular corrosion,accompanied by local homogeneous corrosion.The lower self-corrosive potential and larger self-corrosion current density of NC-304 SS in the polarization curves approve the corrosive rate evaluating result.