Organic and inorganic compounds as corrosion inhibitors to reduce galvanic effect for the hybrid structure AA2024-CFPR

The effect of the galvanic corrosion process taking place between aluminium alloy (AA2024-T3) and carbon fiber reinforced plastic (CFRP) immersed in 0.05 M NaCl was studied using organic inorganic compounds as inhibitors. Electrochemical approaches such electrochemical noise analysis (ENA) impedance spectroscopy (EIS) were carried out to evaluate efficiencies 1,2,4-triazole (C2H3N3) cerium nitrate hexahydrate (Ce(NO3)3·6H2O) highest efficiency reached for Ce(NO3)3.6H2O, with some improvement observed by adding C2H3N3 a mixed inhibitor solution. resistance (Rn) polarization (Rp) values calculated from ENA EIS data showed almost identical behavior different magni­tudes but similar trends. Adsorption isotherm models estimated fractional surface coverage (q) parameter fitted better Langmuir model Temkin Ce(NO3)3·6H2O. Gibbs free energy suggested physi­sorption chemisorption spontaneous interactions metal both Energy-dispersive X-ray (EDS) before after immersing AA2024-T3 electrolyte, identifying rich zones copper deposited over it confirming presence rare-earth oxide deposition film products. EDS CFRP revealed Ce Al particles its immersion especially areas carbon.