Effect of Electrolyte in Microarc Oxidation on Providing Corrosion Resistance to Inhomogeneous Microstructure in ZM21 Magnesium Alloy

Microarc oxidation (MAO), an electrochemical process that employs aqueous electrolytes, is adopted to impart corrosion resistance to magnesium alloys. To study the influence of the inhomogeneity in the microstructure on the characteristics of the coating and therefore on the properties, the weld of...

Full description

Saved in:
Bibliographic Details
Published in:Transactions of the Indian Institute of Metals 2019-06, Vol.72 (6), p.1617-1620
Main Authors: Ram Kumar, V., Muthupandi, V.
Format: Article
Language:English
Subjects:
Alloys
Aqueous electrolytes
Base metal
Chemistry and Materials Science
Corrosion and Coatings
Corrosion effects
Corrosion resistance
Corrosion resistant alloys
Electrolytes
Inhomogeneity
Magnesium base alloys
Materials Science
Metallic Materials
Microstructure
Oxidation resistance
Protective coatings
Substrates
Technical Paper
Tribology
Weld metal
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Microarc oxidation (MAO), an electrochemical process that employs aqueous electrolytes, is adopted to impart corrosion resistance to magnesium alloys. To study the influence of the inhomogeneity in the microstructure on the characteristics of the coating and therefore on the properties, the weld of a ZM21 alloy was considered. The surfaces of the weld metal and the base metal were treated using MAO with silicate and phosphate-based electrolytes. Corrosion behavior of the coated and uncoated base metal and weld metal in 0.1M NaCl was compared using potentiodynamic polarization tests. The results showed that the inhomogeneity in the microstructure of the substrate altered the nature of the coatings and their corrosion resistance was not the same for the electrolytes used in MAO. While for the silicate-based electrolyte, the coated weld metal showed better corrosion resistance than the base metal; a reversal in the corrosion property was noticed with phosphate-based electrolyte.
ISSN:0972-2815
0975-1645
DOI:10.1007/s12666-019-01707-y