Influence of nano-alumina sealing treatment on corrosion resistance of Fe-based amorphous coatings
Anti-Corrosion Methods and Materials
ISSN: 0003-5599
Article publication date: 18 March 2022
Issue publication date: 14 April 2022
Abstract
Purpose
The purpose of this paper is to investigate the effect of nano-alumina sealant sealing treatment on corrosion behavior of the Fe-based amorphous coatings deposited on 304 stainless steel plates by atmospheric plasma spraying (APS) with different hydrogen flow rates.
Design/methodology/approach
The surface morphology and microstructure of the unsealed and sealed coatings were characterized by scanning electron microscopy and X-ray diffraction. The corrosion resistance of the coatings was investigated by potentiodynamic polarization test and electrochemical impedance spectroscopy experiment in 3.5 Wt.% NaCl solution.
Findings
Results show that a few microcracks and pores exist in the as-sprayed Fe-based amorphous coatings. The pores on the surface of the coatings after sealing treatment have been filled with nano-alumina sealant, which can effectively prevent corrosive medium from entering into coatings. Electrochemical tests results show that the corrosion resistance of the coatings before sealing treatment decreases with the increase of hydrogen flow rate and is significantly improved by sealing treatment.
Originality/value
The effect of nano-alumina sealant sealing treatment on corrosion resistance of APS-sprayed Fe-based amorphous coatings is revealed. The corrosion resistance of the as-sprayed Fe-based amorphous coating can be significantly improved by nano-alumina sealant sealing treatment because of the blocking effect of nano-alumina sealant on corrosive medium, which confirms that the application of nano-alumina sealant sealing treatment is of a practical option to improve corrosion resistance of as-sprayed thermal sprayed coatings.
Keywords
Acknowledgements
The financial supports of the China Postdoctoral Science Foundation (Grant No. 2020M671619), the Natural Science Foundation of Jiangsu Province (Grant No. BK20200939), the National Key Research and Development Program of China (Grant No. 2018YFA0704604), the Postdoctoral Science Foundation of Jiangsu Province (Grant No. 2020Z450) and the Natural Science Foundation of the Jiangsu Higher Education Institutions of China (Grant No. 18KJB430030) are gratefully acknowledged by the authors.
Citation
Wei, X., Fu, E., Ban, A., Zhu, W., Wu, D., Li, N. and Zhang, C. (2022), "Influence of nano-alumina sealing treatment on corrosion resistance of Fe-based amorphous coatings", Anti-Corrosion Methods and Materials, Vol. 69 No. 3, pp. 253-260. https://doi.org/10.1108/ACMM-09-2021-2545
Publisher
:Emerald Publishing Limited
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