Multilayers of Ti doped diamond-like carbon (Ti-DLC) coatings were deposited on aluminum alloys by filtered cathodic vacuum arc (FCVA) technology using C₂H₂ as a reactive gas. The effect of different Ti transition layer thicknesses on the structure, mechanical and adhesion properties of the coatings, was investigated by scanning electron microscopy (SEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), nanoindentation and a scratch tester. The results showed that the Ti transition layer could improve interfacial transition between the coating and the substrate, which was beneficial in obtaining excellent adhesion of the coatings. The Ti transition layer thickness had no significant influence on the composition and structure of the coatings, whereas it affected the distortion of the sp²-C bond angle and length. Nanoindentation and scratch test results indicated that the mechanical and adhesion properties of the Ti-DLC coatings depended on the Ti transition layer thickness. The Ti transition layer proved favorable in decreasing the residual compressive stress of the coating. As the Ti transition layer thickness increased, the hardness value of the coating gradually decreased. However, its elastic modulus and adhesion exhibited an initial decrease followed by an increasing fluctuation. Among them, the Ti-DLC coating with a Ti transition layer thickness of 1.1 μm exhibited superior mechanical properties.

Graphene oxide–titanium (GO-Ti) composite materials were fabricated using GO as a precursor and then anchoring nano titanium (Nano-Ti) particles on GO sheets with the help of a silane coupling agent. Then, the coating samples were prepared by dispersing GO, Nano-Ti particles, and GO-Ti in an epoxy resin at a low weight fraction of 1 wt %. The GO-Ti composites were investigated by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The dispersibility and anti-corrosion mechanism of the coatings were studied by sedimentation experiments, electrochemical impedance spectroscopy (EIS), SEM, and salt spray tests. The mechanical properties of the coatings were analyzed by friction and wear tests. The results showed that the Nano-Ti particles were successfully loaded on the GO surface by chemical bonds, which made GO-Ti composites exhibit better dispersibility in the epoxy than GO. Compared with Nano-Ti particles and GO, the GO-Ti composite exhibited significant advantages in improving the corrosion resistance of epoxy coatings at the same contents, which was attributed to the excellent dispersibility, inherent corrosion resistance, and sheet structure. Among the different proportions of composite materials, the GO-Ti (2:1) material exhibited the best dispersibility and corrosion resistance. In addition, the composite material also greatly improved the wear resistance of the coating.

SiC was modified by fluorine-containing organic substance 1H,1H,2H,2H-trifluoro-noctyltriethoxysilane (FAS) to change its hydrophilicity from hydrophilic to superhydrophobic nanoparticles, and the optimum conditions for hydrophobicity were effectively explored. Then, different content of fluorine-modified SiC (F–SiC) nanoparticles were added to the epoxy resin (EP) matrix to prepare composite coating samples. The results showed that the surface of SiC was modified by FAS to show superhydrophobicity, and the dispersion in EP was significantly improved. After adding F–SiC, the hydrophobicity, wear resistance and corrosion resistance of the coating were significantly improved. In addition, the corrosion resistance of the composite coating containing different contents of F–SiC was analyzed through electrochemical and salt spray tests. The results showed that the corrosion resistance of the coating was the best when the addition amount was 3 wt %. In general, the composite coating with 3 wt % F–SiC had the best overall performance. Compared with the EP coating, the water contact angle of 3 wt % F–SiC/EP composite coating was increased by 62.9%, the friction coefficient was reduced by 73.5%, and the corrosion current was reduced by three orders of magnitude. This study provides a new idea for the development of ultra-wear-resistant and anti-fouling heavy-duty coatings.