Effect of fluorinated graphene addition on the microstructure and properties of supercritical Ni/FG composite electrodeposited layers

• Published in: Surface & coatings technology 2025-02, Vol.498, p.131848, Article 131848
• Main Authors: Xue, Ziming, He, Bin, Zhong, Haoyu, Cong, Mengqi, Lei, Weining
• Format: Article
• Language: English
• Subjects: Coefficient of friction; Electrochemical properties; Microhardness; Wear resistance
• ISSN: 0257-8972
• DOI: 10.1016/j.surfcoat.2025.131848

Fluorinated graphene (FG) is widely utilized as a lubricant due to its retention of the intrinsic graphene structure and its unique self-lubricating properties. However, the presence of internal fluorine atoms imparts a highly hydrophobic nature to FG, thereby hindering its effective dispersion in aqueous deposition fluids. To address this challenge, supercritical CO₂ fluid was integrated with electrodeposition technology to facilitate the uniform dispersion of FG in composite electrodeposition solutions. This study primarily investigates the effects of varying FG concentrations on the surface morphology, microstructure, wear resistance, and electrochemical properties of nickel-based fluorinated graphene (Ni/FG) composite electrodeposited coatings. The results indicate that the Ni/FG composite coating, when prepared with an FG concentration of 0.20 g/L, exhibited a smooth surface with no distinct protrusions, alongside a more pronounced grain orientation along the (111) crystal plane and a refined grain size. Moreover, the deposited layer demonstrated a notable microhardness of 775.4 HV₀.₂, while its low coefficient of friction and wear volume suggest robust wear resistance. Electrochemical characterization further confirmed the superior corrosion resistance of the coating. These findings not only introduce a novel approach for the fabrication of FG composite electrodeposited coatings but also provide insights into the potential for enhancing the wear resistance of composite electrodeposited layers through the optimization of second-phase additives. •When the FG was 0.20 g/L, the property of the Ni-FG deposited layer was excellent.•The surface of the deposited layer is flat with no visible bumps.•High degree of grain refinement and small grain size of the deposited layer.•FG particles significantly improve the wear resistance of the deposited layer.•The deposited layer has a high impedance value and good corrosion resistance.