Enhanced surface properties of austenitic stainless steel by electropulsing-assisted ultrasonic surface rolling process

• Introduced electropulsing into the ultrasonic surface rolling process firstly.
• Electropulsing can facilitate the surface cracks healing effectively.
• Electropulsing can bring higher surface hardness or greater impact depth under different experimental parameters.
• A new potential explanation based on electroplastic effect was given.

The present work reports the experimental observations of surface property enhancement for austenitic stainless steel treated by electropulsing-assisted ultrasonic surface rolling process (EP-USRP). Compared with the original ultrasonic surface rolling process (USRP), the introduction of electropulsing can facilitate the surface cracks healing, and alter the cross-sectional micro-hardness gradient distribution within the surface strengthened layer, i.e. significantly gaining higher surface hardness or greater impact depth under the different experimental parameters. Refined grain and enhanced plastic deformation caused by electropulsing are likely the primary reason for the observed phenomena.