Journal
APPLIED SURFACE SCIENCE
Volume 255, Issue 16, Pages 7115-7120Publisher
ELSEVIER SCIENCE BV
DOI: 10.1016/j.apsusc.2009.02.087
Keywords
Magnesium alloy; Microarc oxidation; Coatings; Corrosion test
Categories
Funding
- Inner Mongolia Autonomous Region, P. R. China [20040202]
Ask authors/readers for more resources
Ceramic coatings were fabricated on AZ91D Mg-alloy substrate by microarc oxidation in Na2SiO3-NaOH-Na-2 EDTA electrolytes with and without C3H8O3 addition. The effects of different concentrations of C3H8O3 contained in the electrolyte on coatings thickness were investigated. The surface morphologies, RMS roughness, phase compositions and corrosion resistance property of the ceramic coatings were analyzed by scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), and electrochemical corrosion test respectively. It is found that the addition of C3H8O3 into silicate electrolyte leads to increase of the unit-area adsorptive capacity of the negative ions at anode-electrolyte interface and thus improves the compactness and corrosion resistance of the MAO coating. The coating thickness decreases gradually with the increase of concentrations of C3H8O3 in the electrolyte. The oxide coating formed in base electrolyte containing 4 mL/L C3H8O3 exhibits the best surface appearance, the lowest surface RMS roughness (174 nm) and highest corrosion resistance. In addition, both ceramic coatings treated in base electrolyte with and without C3H8O3 are mainly composed of periclase MgO and forsterite Mg2SiO4 phase, but no diffraction peak of Mg phase is found in the patterns. (C) 2009 Elsevier B. V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available