Mithal, A., Idapalapati, S., & Ramesh, T. (2025). Effect of laser surface annealing on surface topography, microstructure and residual stress of hammer peened 316L stainless steel. Materials Today Communications, 48, 113310. https://doi.org/10.1016/j.mtcomm.2025.113310
Abstract:
In this work, laser annealing is investigated as an alternative to conventional furnace-based heat treatment for 316L stainless steel. Blocks of 316L steel were first hammer peened to induce a residual stress (RS) field after which they were subjected to laser annealing (LA) using various laser powers ranging from 200 to 500 W. The resulting RS, microstructures and surface morphology were characterized using centre hole drilling, electron back scatter diffraction (EBSD) and confocal microscopy, respectively. RS measurements showed that peak compressive RS was reduced from −961 MPa to −488 MPa using a laser power of 500 W. Due to localized surface melting, LA also induced a near surface tensile RS of 437 MPa on average. This surface melting also caused an increase in surface roughness from 1.06 μm Ra in the HPed condition to 3.60 μm Ra after annealing at the highest laser power (500 W). Misorientation analysis revealed that the mechanism of RS is quite different in LA from furnace-based heat treatment. The results indicate the utility of LA for spatial tailoring of RS and microstructures in the near surface regions.
License type:
Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0)
Funding Info:
There was no specific funding for the research done