Applying ANOVA to Study the Effect of Weight Factions of the Nano-Hafnia Dispersed in Spin Coated Gelatin on the Corrosion Behaviour of AISI 316L Steel

This study aims to examine the potential improvement of uniform corrosion resistance and critical pitting potential of AISI 316L stainless steel (SS) in a simulated marine environment containing 3.5 wt. % NaCl by applying layer of gelatin containing HfO2 nanoparticles using spin coating. Also, to examine the statistical significance of using different weight fractions of HfO2 in the applied layer on the corrosion protection performance. The corrosion performance was assessed from potentiodynamic polarization. X-ray diffraction (XRD) was used to check the presence of HfO2 in gelatin matrix. Scanning electron microscopy (SEM), and energy dispersive X-ray analysis (EDX) were used to examine the surface morphology and elemental composition of corrosion products. The results showed that the applied nanocomposite coatings enhanced both uniform and localized corrosion resistance of the underlying AISI 316L SS, also Analysis of Variance (ANOVA) test approved that the weight fractions of dispersed HfO2 nanoparticles have a statistical significant effect on the corrosion performance. Nanocomposites coating having 2 wt.% of HfO2 showed the best performance as compared to other examined coatings.