Nanosecond-pulsed laser ablation as a universal method for oxide removal and surface structuring of aluminum and copper for advanced manufacturing applications

Laser surface texturing enables precise control of micro- and nano-scale topographies that govern wettability, adhesion, friction, and interfacial bonding. In this study, nanosecond-pulsed laser ablation under oxygen-free processing conditions is established as a scalable and automation-ready approach for the simultaneous removal of native oxides and the functional texturing of aluminum and copper surfaces for advanced manufacturing applications. By systematically varying pulse overlap, surface morphologies are tuned from isolated ablation craters to homogeneous textures and, at high overlap, to a melt-dominated regime with increased roughness and effective surface area, enabling application-specific tailoring of interfacial properties. Material-dependent near-surface modifications are observed: aluminum exhibits increased hardness and stiffness, while copper shows localized softening, highlighting fundamentally different laser–matter interaction mechanisms relevant for surface engineering. Microstructural evolution and residual stress development depend on overlap and accumulated fluence, with high overlap promoting texture reduction and stress relaxation. X-ray photoelectron spectroscopy confirms effective oxide removal and exposure of metallic copper under oxygen-free conditions, while identical processing in air leads to pronounced reoxidation; aluminum shows the same qualitative trend. The functional relevance of laser-textured, oxide-free surfaces is demonstrated for adhesive bonding, cold roll bonding, compound casting, and laser beam brazing, enabling improved wetting, enhanced interfacial adhesion, reduced critical deformation for solid-state bonding, and flux-free aluminum–copper joining. The results establish oxygen-free ns-pulsed laser ablation as a versatile surface engineering route that integrates cleaning, oxide-removal and functional structuring in a single step, offering broad potential for advanced and automated manufacturing in joining processes.