Evaluation of Influence Factors for Galvanic Corrosion Coupled between Carbon Fiber Cloth and Carbon Steel

Abstract

Carbon fiber-reinforced plastic （CFRP）-strengthened steel structures are susceptible to galvanic corrosion, especially in high-humidity and marine environments. This study evaluated the key factors influencing galvanic corrosion coupled between carbon fiber and common steel. These factors include the specific electrochemical properties of unidirectional carbon fiber （CF） materials, contact mode between dissimilar materials, and environmental temperature. The results reveal that the carbon filaments and tows were considered physically homogeneous resistors in the fiber direction. However, the surface resistance drops significantly when the CF cloth is in flat contact with a rough conductive metal surface because of the optimized conductive path and enhanced electric contact area. Moreover, based on the Arrhenius equation, this study has developed a simplified model to explain the acceleration effect of temperature on CF-steel galvanic corrosion. It was found that galvanic corrosion is more sensitive to temperature changes than the corrosion of common steel.