Enabling the Reuse of Single-Lap Adhesive-Bonded Joints through Laser Cleaning and Texturing

Adhesive bonding is widely employed for joining complex-shaped components due to its ability to distribute stresses uniformly, preserve material integrity, and eliminate mechanical fasteners. However, the permanent nature of conventional adhesives and the difficulty of clean disassembly hinder the reuse of bonded joints, limiting recyclability and sustainability. This study investigates laser cleaning as an enabling technology for re-bonding single-lap joints. An ultrashort pulsed laser was applied to remove residual epoxy adhesive from AA6061 aluminum alloy substrates after debonding. Surface characterization revealed that laser ablation produces micrometric roughness, and laser processing can be further tailored to generate laser-induced periodic surface structures (LIPSS), influencing morphology, chemistry, and wettability. Mechanical testing demonstrated that laser cleaning also improves the tensile lap-shear strength of re-bonded untreated joints. These findings confirm that laser cleaning effectively restores substrate surfaces and, when combined with controlled texturing, can enhance bonding performance. The proposed approach supports repair and recycling strategies, contributing to extended component lifecycles and circular economy objectives.