Impact of Different Parameters to Enhanced Corrosion Resistance of Zinc-PVDF-G Coating for the Protection of Mild Steel Substrates

This study investigates the corrosion resistance of zinc-PVDF-graphene (zinc-PVDF-G) coatings on mild steel substrates. Coatings with varying graphene concentrations were prepared using electrochemical deposition for zinc, followed by brush coating of PVDF-graphene. Central composite design (CCD) of response surface methodology (RSM) was employed to optimise the coating composition, and high R² values confirmed the reliability of the models. Characterisation using scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transmission spectroscopy (FTIR) demonstrated uniform coating morphology and strong adhesion. The inclusion of 0.9% graphene in PVDF significantly enhanced corrosion resistance, with the P3-coated sample achieving a barrier performance of 5.24 × 10⁶ Ω·cm², an OCP of -0.563 V, and a protection efficiency that improved by approximately 61.6% compared to graphene-free coatings. These results indicate that graphene effectively reinforces the PVDF matrix, reduces diffusion of corrosive species, and provides superior long-term stability, demonstrating the potential of zinc-PVDF-G coatings for high-performance corrosion protection.