Introduction

The invention concerns the use of laser irradiation for the preparation of surfaces of polymers reinforced with carbon fibers (CFRPs). It allows the morphology and chemistry of surfaces to be modified and contaminants to be removed. Through a fast and automated process it is therefore possible to favor the subsequent structural bonding of the parts.

Technical features

Pulsed laser irradiation is employed as surface pre-treatment for adhesive joints comprising carbon fiber reinforced adherents. Trench-shaped patterns generated using pulsed laser exert a toughening effect for the joints thanks to fiber and adhesive ligaments bridging. Pulsed laser irradiation is used for the pre-treatment of composite material adherents. The resulting surface patterns exert a toughening effect on the joints because of the formation of adhesive ligaments that generate a “bridging” effect. Benefitting from the fast processing and micro-scale resolution, the proposed laser process represents an environmentally friendly technology to tailor the toughness of composite joints for a variety of applications.

Possible Applications

• Facilitation of the CFRPs bonding process (secondary bonding);
• Bonding of CFRP patches for structural repairs;
• Bonding of structural components in the automotive and aerospace fields;
• Metal / composite hybrid joints.

Advantages

• Removal of contaminants are not operator dependent;
• Easy implementation and scalability;
• Fast, controllable and ecological process.