Treatment of an epoxy-resin by eximer laser radiation

The surface of carbon fibre reinforced plastics is usually cleaned prior to adhesive bonding. If epoxy resins are the matrix materials, grinding is the most often used procedure. Laser treatment seems to be a more reproducible alternative. In this paper the influence of eximer laser radiation (248 nm) on the surface properties of an epoxy resin is shown. At low laser energy densities the lap shear strength with the epoxy based adhesive Hysol(R) EA 9394 is on an appropriate revel with an improved reproducibility, but at higher energy densities the lap shear strength decreases caused by the formation of a surface layer with a lower strength. This is caused by the decomposition of the resin surface, which is shown by XPS. (C) 1998 Elsevier Science Ltd. All rights reserved.