Impact of atmospheric pressure plasma treatment on surface metallization of CFRP composites

Abstract

Abstract Carbon fiber reinforced composites (CFRP) were activated by atmospheric pressure plasma source to improve the performance of galvanically plated Cu layer on its surface. Plasma activation was done by use of diffuse coplanar surface barrier discharge. Owing to its fabric structure, the morphology and chemical composition of CFRP structure is inherently heterogeneous. Therefore, the attention has been paid to mutual comparison of plasma induced chemical changes and the actual performance of metalized layers at morphologically distinct areas of CFRP surface. To evaluate these performances the XPS, FTIR, determination of surface free energy, nanoindentation, SEM and scratch tests were employed. The chemical analysis confirmed that the positive effect of plasma pre-treatment can be attributed to the introduction of the polar oxygen containing groups: -C=O and -O-C=O into the thin topmost epoxy resin areas, and –C-OH into thick inter-yarn epoxy resin areas. The results also showed that optimized plasma activation can mitigate the adhesion differences between the distinct surface structures.