Improving the oxidation resistance of SIMP steel to liquid Pb-Bi eutectic by shot peening treatments

[Display omitted] •Shot peening improves the oxidation resistance of SIMP steel to liquid Pb-Bi alloy.•Enhanced Cr-rich belts appear in the Fe-Cr spinel of the shot peened SIMP steel.•The oxide of the shot peened SIMP steel has smaller grains and higher compactness.•Pb permeates to a lower extent in the oxides of the shot peened SIMP steel.•The bonding strength of the oxide of shot peened SIMP steel is higher. A gradient nano- and submicron-structured surface layer of SIMP steel was produced by means of shot peening (SP). Compared with the original samples, corrosion experiments at 550℃ for various durations (120 h-1218 h) in liquid LBE showed that the oxidation resistance of the SP samples is significantly improved by shot peening, owing to the enhanced diffusivity of Cr by the large number of grain boundaries and dislocations introduced by shot peening, making it easier to form enhanced Cr-rich oxides. The magnetite layer of the SP samples has higher compactness, giving it better resistance to exfoliation than that of CG samples.