Abstract
Nanosecond laser-shock peening (LSP) was applied at single spots with up to 20 shots on stainless steels (SS304L and SS316L). Interestingly, it was found that the depth of the craters increased almost linearly with the number of LSP shots, and the rates were ∼ 6.6 and ∼ 10.8 μm/shot on SS304L and SS316L, respectively. Micro surface spallation surrounded by outward extrusions was observed at the crater center. Chemical and Raman analyses revealed a presence of carbon oxides and an absence of any LSP-induced metal oxidation at the crater center. However, LSP-induced γ-to-ε transformation occurred along with the presence of α'-martensite in the crater on SS304L rather than on SS316L, providing direct evidence for ε-mediated martensite transformation. The LSP-induced ε/α' ratio was significantly higher than that induced by robotic hammer peening (RHP) at similar depth. These differences are attributed to stacking fault energy and different plastic deformation mechanisms associated with LSP and RHP.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: 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.
