Influence of an oxidation of the carbon fiber surface on the adhesion strength in carbon fiber-acrylate composites cured by electron beam

Oxidized and non-oxidized carbon fibers were used to investigate the influence of an oxidation surface treatment on the adhesion strength with an acrylate resin cured by electron beam. For each type of fiber, a complete characterization of the surface properties was done (topography at a nanometric scale, specific surface area, X-ray photoelectron spectroscopy analysis and dispersive and polar components of the surface energy). The adhesion strength was measured by a pull-out test. For comparison, an isothermal UV curing of the matrix was also investigated. The value of the interfacial shear strength, determined by Greszczukʹs model, was increased by the oxidation of the carbon fiber surface in the case of UV curing. In the case of electron beam curing, low values were obtained for both types of fibers, which could be explained by an incomplete cure of the matrix at the interface.