Comparative study on the impact behavior and damage tolerance of woven carbon fiber reinforced thermoplastic- and thermosetting composites
Résumé
The purpose of this study is to compare the response of TS-based (epoxy) and TP-based (PPS or PEEK) laminates under low velocity impacts. In order to assess the development of internal damage caused by the different impact energies, non-destructive examinations were done. Impact tests created pyramidal-shaped damage at the center of the specimen, extensive delamination and fiber breakages inside laminates, as well as inter laminar and intra-ply damage. CAI tests showed that PEEK-based composites display the best performance, and the compressive residual strengths of C/PPS and C/Epoxy are the lowest for every impact energy. It turns out that the three materials display a rather similar behavior at increasing impact energy as delaminated areas are larger in C/Epoxy and C/PEEK, whereas the PPS matrix toughness contributes to a less extended delaminated area. One reason for the disappointing residual strength of TP-based composites may be the constraint on the development of the plastic deformation zone in the resin rich area between the woven-plies and at the fiber bundles crimp, preventing the matrix toughness to give to the laminates a better damage tolerance.