Effect of hydrogen charging current density on hydrogen damage sensitivity of laser-peened 316L stainless steel

Purpose This study aims to investigate the impact of laser peening on the surface microstructure of 316L stainless steel and the hydrogen damage after electrochemical hydrogen charging at various hydrogen charging current densities. Design/methodology/approach This paper studies the hydrogen damage behavior of laser-peened 316L stainless steel. The research uses scanning electron microscope/electron backscatter diffraction (SEM/EBSD), energy dispersive spectroscopy (EDS), electrochemical hydrogen charging, electrochemical testing, X-ray photoelectron spectroscopy (XPS) to study the microstructure and hydrogen damage characteristics of laser-peened 316L. Findings Laser peening refines the grain size and increases the number of low-angle grain boundaries. The stress-affected layer after laser peening at a power density of 6.4 GW/cm² is approximately 550 µm. In a hydrogen-rich environment, the hydrogen absorption capacity of laser-peened 316L is lower than that of non-peened 316L, and it also enhances the corrosion resistance of 316L stainless steel. Practical implications Provide data reference for the hydrogen damage performance of laser peened 316L stainless steel; provide experimental basis for the hydrogen corrosion reaction of laser peened 316L stainless steel long-term in a hydrogen-rich environment. The findings can be applied in the manufacturing and energy industries to improve product reliability in hydrogen environments, reduce hydrogen corrosion risks and ensure industrial safety. Social implications This research can enhance the durability of stainless steel in hydrogen environments and promote the development of energy and materials science. By optimizing material properties through laser peening technology, it can be applied in hydrogen energy and hydrogen storage technologies, facilitating the development of renewable energy and improving industrial safety. Originality/value This paper provides data support for the corrosion of 316L stainless steel after laser peening in a hydrogen-containing environment.