Behaviour of Couples of Aluminium and Plastics Reinforced with Carbon Fibre in Aqueous Salt Solutions

Reaction potential measurements have been made on a range of carbon fibre reinforced plastic (CFRP) materials in aqueous chloride solutions. In 5% aqueous NaCl the CFRP slowly reached an equilibrium potential, normally about 300 mV positive to SCE. No correlation of potential with the type of carbon fibre or the resin matrix of the CFRP was found. The potential of aluminium and aluminium alloys is about 600–700 mV negative to SCE.

Polarisation studies showed that for CFRP – aluminium alloy couples the polarisation occurs almost exclusively at the CFRP. Very high corrosion currents are passed in aqueous chloride solutions. The effects of chloride ion concentration, pH, temperature, oxygen concentration, and nature of cations and anions in solution have been briefly studied.