Corrosion Resistance of Modified Hexagonal Boron Nitride (h-BN) Nanosheets Doped Acrylic Acid Coating on Hot-Dip Galvanized Steel

• Main Authors: Yongzhe Fan, Huazhen Yang, Haisheng Fan, Qi Liu, Chuang Lv, Xue Zhao, Mingxu Yang, Jianjun Wu, Xiaoming Cao
• Format: Article
• Language: English
• Published: MDPI AG 2020-05-01
• Series: Materials
• Subjects: hot-dip galvanized steel; boron nitride nanosheet; corrosion resistance; acrylic coating
• Online Access: https://www.mdpi.com/1996-1944/13/10/2340

The hexagonal boron nitride (h-BN) nanosheets modified by silane coupling agent (KH560) were doped into acrylic acid coating on the surface of galvanized steel to improve its corrosion resistance. H-BN nanosheets modified by KH560 were prepared and characterised by scanning electron microscopy, transmission electron microscopy, atomic force microscopy, X-ray diffraction, and Fourier-transform infrared spectroscopy. The corrosion resistance of the acrylic acid coatings was measured by electrochemical testing. The results show that the corrosion current density of the coating with modified h-BN nanosheets was reduced from 2.2 × 10⁻⁵ A/cm²to 2.3 × 10⁻⁷ A/cm² compared with the acrylic acid coating. The impedance of the composite coating with modified h-BN is 4435 Ω·cm², higher than the BNNS coating (2500 Ω·cm²) and the acrylic acid coating (1500 Ω·cm²). This is due to the physical barrier and electrical insulation properties of the hexagonal boron nitride (h-BN) nanosheets.