Research status of laser surface texturing on tribological and wetting properties of materials: A review

Laser surface texturing (LST) holds great potential in fabricating precise and controllable micro/nanostructures, benefiting from its high processing resolution, flexible processing methods, and capability to handle a wide range of materials. This paper aims to comprehensively review the research status of LST in improving materials' friction and wetting properties. Firstly, the significance of friction and wetting properties is outlined, followed by an introduction to commonly employed LST, including laser ablation, laser interference, and laser shock processing. Then, much emphasis has been placed on the impact of laser parameters and texture design on material properties. By manipulating laser parameters such as pulse width, pulse power density, and number of pulses, different effects can be generated on the geometric characteristics, pattern types, and distribution forms of surface textures, thereby altering the surface's microscopic topography, roughness, hardness, and wettability to exhibit different friction and wetting performances. Next, the optimization methods for texture performance are discussed, encompassing the optimization of laser parameters and the texture itself. In particular, the fundamental theories and influencing mechanisms of LST on materials' friction and wetting performance are elaborated in detail, followed by an overview of research conducted on metals, non-metals, and composite materials. Finally, a summary is provided on the application of LST in improving the friction and wetting performance of materials while pointing out the limitations of existing research and prospects for future research directions.