Influence of the carbon fiber surface properties on interfacial adhesion in carbon fiber–acrylate composites cured by electron beam

Two different commercial references of oxidized carbon fibers were used to investigate the influence of different oxidation surface treatments on the interfacial adhesion with an acrylate resin cured by electron beam. For each type of fiber, a characterization of the topography and the chemistry of the surface was done. The 90° flexural strength of unidirectional composites was measured in order to assess interfacial adhesion. Low values were obtained for both types of fibers, which could be explained by the creation of a weak interphase, which was highlighted by a dramatic improvement of the flexural strength after a post-cure. That interphase could be the origin of the low transverse mechanical properties of electron beam cured composites.