Influence of gelatin-TiO2-Al2O3 nanocomposite coatings on enhancement of wear and corrosion resistance of SKD11 steel

Abstract

The performance and lifespan of steel mechanical components that experience wear and corrosion hinges on their surface properties, such as wear resistance, hardness, and corrosion resistance. Therefore, a surface coating method is vital to enhance the surface properties of this material. In this study, the influence of gelatin-TiO2-Al2O3 (GTA) nanocomposite coatings on the wear and corrosion resistance of the SKD11 steel (SS) surface was investigated with the purpose of enhancing the lifespan of this material. The nanocomposite coatings were prepared using a sol-gel spin-coating method. Microscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and contact angle measurements were used to analyze the surface morphology, molecular interactions, microstructure, and wettability of the coatings. The corrosion resistance is also determined by electrochemical tests in simulated body fluid (SBF), although the wear properties are evaluated using a ball-on-disc tribotester. Subsequently, a comparative analysis of pure gelatin (G) G-coated and uncoated samples is performed. These results confirm the formation of homogeneous, crack-free, and defect-free coatings on the substrates. Compared to the G-coated and uncoated samples, the anti-wear and anti-corrosion performances of the substrates were noticeably enhanced by the incorporation of gelatin and TiO2–Al2O3 coatings, structural advantages, and hydrophilicity. Furthermore, compared with the uncoated sample, the prepared GTA sample improved the friction coefficient and wear rate of the substrates by 45.16 % and 39.19 %, respectively.