A comprehensive investigation on wear and corrosion performance of AISI 8620 steel after severe vibratory peening

In this study, the effect of Severe Vibratory Peening (SVP), a surface severe plastic deformation method, on the microstructure and mechanical performance of AISI 8620 steel was investigated. Specimens were treated with SVP for 30 minutes, 1 hour, 2 hours, and 4 hours. Microstructural analysis revealed that all treatments induced a plastic deformation layer on the surface, with layer thickness increasing with longer treatment durations. Surface microhardness increased by 22% relative to untreated specimens, with improvements observed up to approximately 85 μm beneath the surface. Under a 5 N load, wear volume loss showed no significant difference between treated and untreated specimens; however, at a 15 N load, long-term SVP treatments (1, 2, and 4 hours) resulted in decreased wear loss compared to the untreated condition. The enhanced hardness from plastic deformation overcame the negative effects of increased surface roughness on wear resistance. Moreover, the coefficient of friction decreased with increasing load in the treated specimens, although untreated specimens exhibited the lowest friction overall. Corrosion resistance improved following all SVP treatments, with the highest resistance observed in the 30-minute treatment and the lowest in the untreated specimen.