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

TL;DR

This study shows that adding graphene to zinc-PVDF coatings significantly improves their ability to protect mild steel from corrosion.

Contribution

The novel contribution is the optimization of graphene concentration in zinc-PVDF coatings to enhance corrosion resistance using response surface methodology.

Findings

A 0.9% graphene concentration in PVDF significantly improved corrosion resistance with a barrier performance of 5.24 × 10⁶ Ω·cm².

Protection efficiency increased by 61.6% compared to coatings without graphene.

SEM, XRD, and FTIR confirmed uniform morphology and strong adhesion of the optimized coating.

Abstract

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.

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