Exploring Galvanic Corrosion Behavior of CFRP/Q235 Carbon Steel in Marine Environment

Abstract

Carbon fiber reinforced polymer (CFRP), known for its high modulus and lightweight properties, holds significant promise in the field of ocean engineering. However, the beneficial potential of CFRP is often compromised when in contact with metals. This work examines the galvanic corrosion behavior of a CFRP/Q235 carbon steel couple typical of bolted assemblies, using electrochemical measurements, immersion tests and finite element modeling (FEM). The findings reveal that the surface and cross-section of CFRP exhibit differing electrochemical activities, with the cross-section demonstrating more severe corrosion. The interaction between CFRP and Q235 leads to galvanic corrosion due to the potential difference, with CFRP acting as the cathode, thus accelerating the corrosion of Q235. The extent of galvanic corrosion increases progressively with longer immersion times. XRD analysis identifies FeO(OH) and Fe₃O(OH) as the primary corrosion products on Q235 under both conditions.