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Characteristics of Conversion Coating of AZ31 Magnesium Alloy Formed in Chromium-Free Cerium-Based Solution
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 Title & Authors
Characteristics of Conversion Coating of AZ31 Magnesium Alloy Formed in Chromium-Free Cerium-Based Solution
Kim, Myung Hwan; Lee, Dong Uk; Kwag, Sam-Tag; Moon, Myung-Jun;
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 Abstract
A chromium-free Ce-based conversion coating formed by immersion in a solution containing cerium chloride and nitric acid on AZ31 magnesium alloy has been studied. The effects of acid pickling on the morphology and the corrosion resistance of the cerium conversion coating were investigated. The corrosion resistance of the conversion coating prepared on AZ31 Mg alloy after organic acid pickling was better than that of inorganic acid pickling. The morphology of the conversion-coated layer was observed using optical microscope and SEM. Results show that the conversion coatings are relatively uniform and continuous, with thickness 1.0 to . The main elements of the conversion coating of AZ31 Mg alloy are Mg, O, Al, Ce and Zn by EDS analysis. The electrochemical polarization results showed that the Ce-based conversion coating could reduce the corrosion activity of the AZ31 Mg alloy substrates in the presence of chloride ions.
 Keywords
AZ31;Magnesium alloy;Conversion coating;Chromium- free;Acid pickling;
 Language
Korean
 Cited by
 References
1.
M. Avedesian, H. Baker, Magnesium and Magnesium Alloy, ASM Specialty Handbook 12 (1999).

2.
G. L. Song, A. Atrens, Corrosion Mechanisms of Magnesium Alloys, Adv. Eng. Mater., 1 (1999) 11-33. crossref(new window)

3.
D. Peixoto Barbosa, G. Knornschild, Anodization of Mg-Alloy AZ91 in NaOH Solutions, Surf. Coat. Tech., 203 (2009) 1629-1636. crossref(new window)

4.
Z. Liu, W. Gao. A Novel Process of Electroless Ni-P Plating with Plasma Electrolytic Oxidation Pretreatment, Appl. Surf. Sci. 253 (2006) 2988-2991. crossref(new window)

5.
W. X. Zhang, Z. G. He, Z. H. Jiang, J. S. Lian, Electroless Ni-P Layer with a Chromium-Free Pretreatment on AZ91D Magnesium Alloy, Surf. Coat. Tech., 201 (2007) 4594-4600. crossref(new window)

6.
M. Zhao, S. Wu, P. An, J. Luo, Y. Fukuda, H. Nakae, Microstructure and Corrosion Resistance of a Chromium-Free Multi-Elements Complex Coating on AZ91D Magnesium Alloy, Mater. Chem. Phys., 99 (2006) 54-60. crossref(new window)

7.
H. Zhang, G. Yao, S. Wang, Y. Liu, H. Luo, A Chrome-Free Conversion Coating for Magnesium-Lithium Alloy by a Phosphate-Permanganate Solution, Surf. Coat. Tech., 202 (2008) 1825-1830. crossref(new window)

8.
M. Zhao, S. Wu, P. An, J. Luo, Influence of Surface Pretreatment on the Chromium-free Conversion Coating of Magnesium Alloy, Mater. Chem. Phys., 103(2007) 475-483. crossref(new window)

9.
M. Zhao, S. Wu, J. Luo, Y. Fukuda, H. Nakae, A Chromium-Free Conversion Coating of Magnesium Alloy by a Phosphate-Permanganate Solution, Surf. Coat. Tech., 200 (2006) 5407-5412. crossref(new window)

10.
T. Ishizaki, I. Shigematsu, N. Saito, A Chromium-free Conversion Coating of Magnesium Alloy by a Phosphate-Permanganate Solution, Surf. Coat. Tech., 203 (2009) 2288. crossref(new window)

11.
H. Y. Su, W. J. Li, C. S. Lin, Effect of Acid Pickling Pretreatment on the Properties of Cerium Conversion Coating on AZ31 Magnesium Alloy, J. Electrochem. Soc.,159(5) (2012) C219-C225. crossref(new window)

12.
C. E. Castano, M. J. O'Keefe, W. G. Fahrenholtz, Microstructural Evolution of Cerium-based Coatings on AZ31 Magnesium Alloys, Surf. Coat. Tech., 246 (2014) 77-84. crossref(new window)

13.
A. S. Hamdy, M. Farahat, Chrome-Free Zirconia-Based Protective Coatings for Magnesium Alloys, Surf. Coat. Tech., 204 (2010) 2834-2840. crossref(new window)

14.
U. C. Nwaogu, C. Blawert, N. Scharnagl, W. Dietzel, K. U. Kainer, Chrome-Free Zirconia-Based Protective Coatings for Magnesium Alloys, Corros. Sci. 51 (2009) 2544-2556. crossref(new window)

15.
H. H. Elsentriecy, K. Azumi, H. Konno, Effect of Surface Pretreatment by Acid Pickling on the Density of Stannate Conversion Coatings Formed on AZ91D Magnesium Alloy, Surf. Coat. Tech., 202 (2007) 532-537. crossref(new window)

16.
M. Dabala, L. Armelao, A. Buchberger, I. Calliari, Cerium-Based Conversion Layers on Aluminum Alloys, Appl. Surf. Sci., 172 (2001) 312-322. crossref(new window)

17.
M. H. Kim, S. T. Kwag, M. J. Moon, Characteristics Evaluation of Conversion Coating of Acid Pickling AZ31 Magnesium Alloy by a Chromium-Free Phosphate-Permanganate Solution, J. Kor. Surf. Eng. 43(2) (2010) 73-79. crossref(new window)

18.
K. Z. Chong, T. S. Shih, Characteristics Evaluation of Conversion Coating of Acid Pickling AZ31 Magnesium Alloy by a Chromium-Free Phosphate-Permanganate Solution, Mater. Chem. Phys., 80 (2003) 191-200. crossref(new window)

19.
K. Brunelli, M. Dabalà, I. Calliari, M. Magrini, Characteristics Evaluation of Conversion Coating of Acid Pickling AZ31 Magnesium Alloy by a Chromium-Free Phosphate-Permanganate Solution, Corros. Sci., 47 (2005) 989-1000. crossref(new window)

20.
F. H. Scholes, C. Soste, A. E. Hughes, S. G. Hardin, P. R. Curtis, The Role of Hydrogen Peroxide in the Deposition of Cerium-Based Conversion Coatings, Appl. Surf. Sci., 253 (2006) 1770-1780. crossref(new window)

21.
A. A. Aal, Protective Coating for Magnesium Alloy, J. Mater. Sci., 43 (2008) 2947-2954. crossref(new window)

22.
Y. G. Ko, K. M. Lee, K. R. Shin, D. H. Shin, Effect of Potassium Permanganate on Corrosion Behavior of Magnesium Alloy Prepared by Micro-Arc Oxidation, Kor. J. Met. Mater., 48 (2010) 724-729.

23.
M. G. Fontana, Corrosion Engineering, McGraw Hill (1987) 173.