Effect of Aluminium and Magnesium on the Corrosion Resistance of Zinc Coatings

Abstract

This article presents the research on corrosion resistance of Zn-Al-Mg coatings with varying aluminium and magnesium content. Aluminium and magnesium were added directly to the zinc bath at 10:1 rate. There was found more than sixfold increase in corrosion resistance of zinc coatings with aluminium content at the level of 4% of weight and magnesium content at the level of 0.4% of weight. In contrast to the amounts applied in the literature, such content of these alloy additives in the zinc bath limits to a significant extent the amount of intermetallic phases in zinc coatings obtained from such baths. This, in consequence, results in high resistance to corrosion with simultaneous retention of high plasticity of these coatings.

Application of X-ray Diffraction for Residual Stress Analysis in Truncated Cones Made by Incremental Forming

“…cold-rolling process. The deformation of the DC04 sheet in SPIF led to the intensification of the corrosion process [9]. Thus, the low-carbon steel sheets should be protected immediately after forming the anti-corrosion coating.…”

characterization of Zn-Mg-Al based coating

“…The dissolution rate and the difference in corrosion potential between Zn and steel can reduce the use of Zn alloy coating with Ni [8,9], Co [10] or Sn [11]. Currently, Zn-Mg-Al based anti-corrosion coating is being studied [12]. In addition to the increased corrosion resistance, the coatings obtained from these baths have higher hardness and scratch resistance [13].…”

“…The elements added to the zinc bath significantly affect the structure, appearance and corrosion resistance of the resulting coating [12]. Aluminium improves the plasticity of the coating, lightens, increases gloss and improves corrosion resistance by forming a zinc coating containing Al2O3.…”