EFFECTS OF THE ALKALINE PERMANGANATE ETCHING OF EPOXY ON THE PEEL ADHESION OF ELECTROLESSLY PLATED COPPER ON A FIBER-REINFORCED EPOXY COMPOSITE

The adhesion of electroplated copper to a fibre-reinforced epoxy compo site is controlled by mechanical keying. Rough surfaces are prepared b y chemical etching. Therefore mechanical properties could be degraded if the difference in reactivity of the composite components (fibres an d matrix) is not taken into consideration. To eliminate this surface h eterogeneity, a plating film (epoxy resin) is applied to the composite . which becomes chemically homogeneous. During the etching process, th is plating film will protect the integrity of the composite. Later on, copper can be directly electroplated onto the intermediate layer (epo xy resin). This study describes the influence of the surface geometric characteristics of two composites on the adhesion strength of a coppe r coating. We have found that the mean peak-to-valley height (R-z) is nor sufficient to explain the adhesion level. The technique of profilo metric relocation is used for quantifying the etching effect on the su rface micro-geometry, which is dependent on the initial composite subs trate roughness.