Superhydrophilic Hybrid Sol-gel Coating for Improved Corrosion and Surface Properties of AZ31 Mg Alloy

Strategic Insights -

Researchers at Erzincan Binali Yildirim University have developed a superhydrophilic hybrid sol-gel coating that significantly improves the corrosion and surface properties of AZ31 Mg alloy. The study, published in Advanced Engineering Materials, utilized Fourier transform infrared spectroscopy (FTIR), SEM, energy dispersive X-ray spectroscopy, surface hardness, surface roughness, contact angle, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS) tests to investigate the properties of the obtained film. The findings reveal that the hybrid film coating exhibits improved mechanical performance, increased hardness, and enhanced surface properties.

Key Takeaways:

  • The superhydrophilic hybrid sol-gel coating was applied to the surface of AZ31 Mg alloy, resulting in a dense film layer of approximately 1.4 μm thickness.
  • FTIR analysis confirmed the presence of Si-O-Si, Si-OH, and -NH2 functional groups, indicating successful formation of the hybrid structure in the obtained film.
  • The hybrid-coated AZ31 Mg alloy exhibited a significant improvement in mechanical performance, with a 68% increase in surface hardness.
  • The coatings demonstrated high impedance barrier properties, increasing the total polarization resistance by 79 times.
  • The coating also showed superhydrophilic properties, with a low contact angle of 7.85 degrees.

Statistics:

  • 1.4 μm: The thickness of the dense film layer formed by the hybrid film coating.
  • 68%: The increase in surface hardness of the hybrid-coated AZ31 Mg alloy.
  • 79 times: The increase in total polarization resistance provided by the hybrid coating.
  • 7.85 degrees: The low contact angle of the coated film, indicating superhydrophilic properties.

Sources:

  • News Reports: "Findings in Technology Reported from Erzincan Binali Yildirim University (Superhydrophilic Hybrid Sol-gel Coating for Improved Corrosion and Surface Properties of Az31 Mg Alloy)" (Journal of Engineering, October 20, 2025)
  • Advanced Engineering Materials: "Superhydrophilic Hybrid Sol-gel Coating for Improved Corrosion and Surface Properties of Az31 Mg Alloy" (2025)