Evaluation of the protective nature of GO–BCP nanocomposite coatings on 316L SS in artificial body fluid

This work reports on a novel approach to deposit composite coatings based on biphasic calcium phosphate (BCP) incorporating graphene oxide (GO) on 316L stainless steel (316L SS) and on its protective nature against corrosion in the simulated body fluid (SBF). For this purpose, 2-dimensional GO was successfully incorporated in 1% and 3% weight ratios as mechanical strength enhancer and pore size reducer for the prepared coatings. It was observed that upon increasing the GO content, the corrosion rate was drastically decreased when compared to pristine BCP coating. The corrosion resistance polarization results are in good agreement with the test results obtained for SBF immersion study. The size of the particles has significantly decreased, as shown by transmission electron microscopy (from 190 to 27 nm). The experimental results indicate that the composite hydroxyapatite–β-tricalcium phosphate–GO (HAp–β-TCP–GO) coatings enhanced the corrosion resistance of the surgical grade 316L SS, turning it a better implanting option for orthopedic applications.