Measurement of metallic coatings adhesion to fibre reinforced plastic materials

Two tests have been developed to characterise the adhesion of copper coatings to thin carbon fibre reinforced polymer substrates. The multi-layer three-point bending test (ML-TPB) is dimensioned so that the fracture is initiated by an interfacial shear stress. The multi-layer double cantilever beam test (ML-DCB) is a crack propagation test derived from the interlaminar fracture test used for composite materials, giving access to the adhesion energy. Experimental results show that the adhesion of copper coating is not sensitive to the ageing of the thermoplastic bond coat. An optimal coating thickness of 100 μm was determined with regard to the coating adhesion.