A review of physical properties of hot-dip galvanized coating layer by layer and their respective electrochemical corrosion behavior

Abstract

Purpose

This paper aims to contribute to the performance improvement and the broader application of hot-dip galvanized coating.

Design/methodology/approach

First, the ability to provide barrier protection, galvanic protection, and corrosion product protection provided by hot-dip galvanized coating is introduced. Then, according to the varying Fe content, the growth process of each sublayer within the hot-dip galvanized coating, as well as their respective microstructures and physical properties, is presented. Finally, the electrochemical corrosion behaviors of the different sublayers are analyzed.

Findings

The hot-dip galvanized coating is composed of η-Zn sublayer, ζ-FeZn13 sublayer, δ-FeZn10 sublayer, and Γ-Fe3Zn10 sublayer. Among these sublayers, with the increase in Fe content, the corrosion potential moves in a noble direction.

Research limitations/implications

There is a lack of research on the corrosion behavior of each sublayer of hot-dip galvanized coating in different electrolytes.

Practical implications

It provides theoretical guidance for the microstructure control and performance improvement of hot-dip galvanized coatings.

Originality/value

The formation mechanism, coating properties, and corrosion behavior of different sublayers in hot-dip galvanized coating are expounded, which offers novel insights and directions for future research.

Citation

Li, Z., Li, D., Zhou, Y., Peng, H., Xie, A. and Wang, J. (2024), "A review of physical properties of hot-dip galvanized coating layer by layer and their respective electrochemical corrosion behavior", Anti-Corrosion Methods and Materials, Vol. 71 No. 5, pp. 580-589. https://doi.org/10.1108/ACMM-02-2024-2963