Effect of the Addition of Molybdenum on the Structure and Corrosion Resistance of Zinc–Iron Plating

Coatings

Daichi Kosugi¹  Ryoichi Ichino¹  Takeshi Hagio¹  Yuki Kamimoto² 

[1] Department of Chemical Systems Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan;Green Mobility Research Institute, Institutes of Innovation for Future Society, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan;

关键词: Zn–Ni plating;    Zn–Fe plating;    anti-corrosion performance;    Mo addition;    alloy formation;   

DOI  :  10.3390/coatings7120235

来源: DOAJ

【 摘 要 】

Zn–Ni plating is indispensable in various industries because of its high corrosion resistance. However, Ni has been reported to trigger allergies; thus, an alternative Ni-free plating is desired. Zn–Fe plating is considered to be a promising candidate, albeit its corrosion resistance still needs to be improved. The corrosion resistance of Zn–Fe plating is expected to increase by the addition of Mo as the third alloying element as it is more noble than Zn and Fe. In this study, Zn–Fe–Mo plating with a corrosion resistance nearly equivalent to that of the Zn–Ni plating was fabricated. Zn–Fe–Mo plating was electrically deposited from continuously-agitated plating baths prepared by mixing ZnSO4, FeSO4, Na2MoO4, Na3C6H5O7, and Na2SO4 using Fe or Ni plates as the substrate. The surface morphology, composition, crystal phase, and electronic state of Mo of the platings were investigated by scanning electron microscopy equipped with energy-dispersive spectroscopy (SEM-EDS), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The anti-corrosion performance was evaluated by Tafel extrapolation method. Formation of plating comprising a Mo containing alloy phase was found to be crucial for improving corrosion resistance. The Zn–Fe–Mo plating demonstrates promise for replacing anti-corrosion Zn–Ni platings.

【 授权许可】

Unknown