Effects of adhesive strips embedded at the interface in graphite/epoxy laminates on damage tolerance are investigated. Specimens were impact tested under approximately fixed-fixed boundary conditions. Comparisons were made between the specimens with and without the adhesive from X-ray radiographs. Delamination plotted against velocity shows substantially reduced delamination in specimens with adhesive compared with specimens without adhesive. It was observed that below a certain velocity the adhesive acts as a softening strip which confines the delamination to the area of the mesh formed by the adhesive. Three-point-bend tests show that the failure load of plain specimens is higher than for the specimens with adhesive before impact; however, after impact the strength degradation is more severe in the plain specimens. Damage mechanisms of impacted specimens were examined through the use of microphotographs.
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