Table of Contents
Textures and Microstructures
Volume 34 (2000), Issue 2-3, Pages 119-146
http://dx.doi.org/10.1155/TSM.34.119

The Microstructural Characterization of Electrogalvanized Zinc–Iron and Zinc–Nickel Coatings

Department of Metallurgical Engineering, McGill University, 3610 University Street, Montreal, PQ H3A 2B2, Canada

Received 8 October 1999

Copyright © 2000 Hindawi Publishing Corporation. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

In this study, the development of the microstructure of zinc–iron and zinc–nickel coatings on steel sheet electrodeposited at various deposition conditions, is analyzed. The evolution of the coating microstructure – texture, surface morphology, crystallographic lattice, microstress, alloy composition and phase of coatings – is investigated at different current densities and deposition times. The microstructure of zinc alloy coatings varies significantly with the change of deposition parameters. The present study proposes that the transformarion of texture during the alloy codeposition is closely related to the morphological characteristics of the coating surface and the change of alloy and phase composition of the deposit. Anomalous codeposition behavior, is considered responsible for the change or transformation of the microstructure of coatings. The texture of zinc–iron coatings changes from the combined texture of the basal fiber and non-fiber pyramidal component to the pyramidal fiber texture with the current density increase. In the case of zinc–nickel coatings, the intensity of the {101} texture of γ phase increases with increasing nickel content, while the intensity of the {100} texture decreases. A correlation between the texture, morphology and alloy content in the deposits is discussed.