Improving the bond strength of metal-FRP-hybrids with thermal sprayed copper using pulsed laser-based processing approaches

Ablation processes during laser treatment of carbon fiber-reinforced plastics (CFRP) with pulsed lasers of various wavelengths and pulse durations are investigated. Three different surface pre-treatment strategies are used, including laser-roughening, selective matrix removal and laser micro structuring. Various ablation mechanisms, including evaporation and photochemical ablation are reported, dlepending on the employed laser source. Selected laser structured substrates w ere coated with copper by a wire arc spraying process. Bonding strengths up to 18.7 ± 2.0 MPa were achieved in shear tensile tests, by the combination of the roughening process and the micro-structuring approach. Consequently, the bonding strength could be increased over~ 180 % compared to the common pre-treatment by mechanical blasting.