Investigation of the Cleaning Effectiveness of Laser Radiation for Improved Adhesion on Glass Dust Contaminated Glass Fiber Reinforced Polyamide 6
Proceedings in Engineering Mechanics (Research, Technology and Education)
Fiber reinforced polymers (FRP) offer high stiffness and stability properties but are difficult to bond adhesively due to the characteristically low free surface energies of the polymer matrix. In addition, contaminations on the surface act as a barrier and reduce the adhesion between the FRP and the adhesive. Dust is one of the most common surface contaminations and can stem from a variety of sources, especially in industrial environments. To bond FRPs, the surface needs to be clean and contaminations have to be removed from the surface. Laser cleaning represents an innovative method to remove contaminations and simultaneously pre-treat the surface. This work investigates the cleaning effectiveness of 1064~nm laser radiation on a glass fiber reinforced polyamide 6 substrate contaminated with glass dust. The investigations are based on SEM (scanning electron microscopy) investigations, surface energy investigations by contact angle measurement, tensile shear tests, and roller peel tests. The treatment of uncontaminated and contaminated samples is compared. Additionally, for the cleaning process the number of transits was varied. The best parameter for both cleaning and pre-treatment was found to be at a pulse fluence of 0.88~J/cm2.