Galvanic corrosion of polyacrylnitrile (PAN) and pitch based short carbon fibres in polyetheretherketone (PEEK) composites

When an electric current is conducted through a short fibre reinforced polyetheretherketone composite, being in contact with a stainless steel electrode, carbon fibre corrosion occurs. Surface analysis shows that structural defects range from debonding events and fibre cracking in the early stage of the corrosion process to the final disintegration of the fibre. The extent of fibre corrosion is quantified by atomic force microscopy, and the influence of fibre type, fibre volume content and the aqueous medium on the fibre corrosion is reported. Overall, polyacrylnitrile based fibres have a higher corrosion resistance than pitch based ones.