Abstract
Surface nanocrystallization of AISI-1018 steel was successfully realized by ultrasonic shot peening (USSP). The fabricated nanocrystalline surface layer was observed and characterized by means of scanning electron microscope and transmission electron microscope. Experimental evidence indicates that after USSP, the initial coarse-grained structure (~20 lm) at the top surface layer was refined into ultrafine grains with random crystallographic orientation and the elongated grains were observed at the sub-surface layer. Nanograins (~100 nm) and nanocrystalline surface layer with the thickness of 1 lm were fabricated after USSP treatment of 20 minutes. By increasing the USSP treatment duration to 60 minutes, nanograins in the size of 20 nm and nanocrystalline surface layer with the thickness of not less than 10 lm were generated. To predict the generation of nanostructured surface layer by plastic strain, an analytical algorithm cooperating with finite element method was proposed to simulate the strain distribution and surface topography of the peened surface during USSP. The proposed algorithm was verified and the simulation results show a reasonable agreement with the experimental results.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.