Transactions of Materials Processing (소성∙가공)

The Korean Society for Technology of Plasticity and materials processing (한국소성∙가공학회)
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Effect of Subsequent-Annealing Temperature on Surface Properties of Plasma Electrolytic Oxidation-Treated Mg Alloy

플라즈마 전해산화 처리된 마그네슘 합금의 표면 물성에 미치는 후-열처리 온도의 영향

  • 고영건 (영남대학교 신소재공학부) ;
  • 김용민 (한양대학교 금속재료공학과) ;
  • 남궁승 (한양대학교 금속재료공학과) ;
  • 신동혁 (한양대학교 금속재료공학과)
  • Published : 2009.12.01
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Abstract

The influence of the subsequent-annealing(SA) temperature on the plasma electrolytic oxidation(PEO)-treated Mgbased alloy was investigated in terms of surface properties associated with hardness and corrosion. For this purpose, a series of the SA treatments were performed on the PEO-treated samples at four different temperatures, i.e., 100, 150, 200, and $250^{\circ}C$ for 10 hrs. When compared to the sample without SA, the samples annealed at temperatures higher than $200^{\circ}C$ showed a difference in surface morphology due to the volume expansion accompanied by the dehydration reaction where the part of $Mg(OH)_2$ changed into MgO, working as harder phase. From the results of nano-indentation tests, the applied loads of the samples were seen to increase with increasing SA temperatures. However, the electro-chemical and corrosion properties of the sample annealed at $150^{\circ}C$ were higher than those of the samples annealed at three temperatures.

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References

  1. A. L. Rudd, C. B. Breslin, F. Mansfeld, 2000, The corrosion protection afforded by rare earth conversion coatings applied to magnesium, Corros. Sci., Vol. 42, pp. 275-288 https://doi.org/10.1016/S0010-938X(99)00076-1
  2. J. E. Gray, B. Luan, 2002, Protective coatings on magnesium and its alloys, J. Alloys Comp., Vol. 336, pp. 88-113 https://doi.org/10.1016/S0925-8388(01)01899-0
  3. G. Song, A. Atrens, M. Dargusch, 1999, Influence of microstructure on the corrosion of die cast AZ91D, Corros. Sci., Vol. 41, pp. 249-273 https://doi.org/10.1016/S0010-938X(98)00121-8
  4. K. Murakami, M. Hino, K. Nakai, S. Kobayashi, A. Saijo, T. Kanadani, 2008, Mechanism of corrosion protection of Anodized magnesium alloys, Mater. Trans., Vol. 49, pp. 1057-1064 https://doi.org/10.2320/matertrans.MC200718
  5. Q. Cai, L. Wang, B. Wei, Q. Liu, 2006, Electrochemical performance of microarc oxidation films formed on AZ91D magnesium alloy in silicate and phophate electrolytes, Surf. Coat. Technol., Vol. 200, pp. 3727 -3733 https://doi.org/10.1016/j.surfcoat.2005.05.039
  6. O. Khaselev, D. Weiss, J. Yahalom, 1999, Anodizing of pure magnesium in KOH-Aluminate solutions under sparking, J. Electrochem. Soc., Vol. 146, pp. 1757-1761 https://doi.org/10.1149/1.1391838
  7. H. Duan, C. Yan, F. Wang, 2007, Growth process of plasma electrolytic oxidation films formed on magnesium alloy AZ91D in silicate solution, Electrochim. Acta, Vol. 52, pp. 5002-5009 https://doi.org/10.1016/j.electacta.2007.02.021
  8. J. J. Jeon, S.W. Leem, B. H. Kim, B. G. Park, Y. H. Park, I. M. Oark, 2008, Effect of Sb and Sr adding on corrosion properties of Mg-5Al-2Si alloy, J. Kor. Inst. Met. & Mater., Vol. 46, pp. 304-310
  9. H. F. Guo, M. Z. An, H. B. Huo, S. Xu, L. J. Wu, 2006, Microstructure characteristic of ceramic coatings fabricated on magnesium alloys by microarc oxidation in alkaline silicate solutions, Appl. Surf. Sci., Vol. 252, pp. 7911-7916 https://doi.org/10.1016/j.apsusc.2005.09.067
  10. H. G. Kim, Y. H. Jeong, 2008, Evaluation of the corrosion and oxide micristructural characteristics of pure Zr and the Zr-1.5Nb alloy, Met. & Mater. Int., Vol. 14, pp. 83-89 https://doi.org/10.3365/met.mat.2008.02.083
  11. G. L. Song, A. Atrens, 1999, Corrosion mechanism of magnesium alloys, Adv. Eng. Mater., Vol. 1, pp. 11-33 https://doi.org/10.1002/(SICI)1527-2648(199909)1:1<11::AID-ADEM11>3.0.CO;2-N
  12. W. Xiemi, Z. Liqun, L. Huicong, L. Weiping, 2008, Influence of surface pretreatment on the anodizing film of Mg alloy and the mechanism of the ultrasound during the pretreatment, Surf. Coat. Tech., Vol. 202, pp. 4210-4217 https://doi.org/10.1016/j.surfcoat.2008.03.018
  13. H. Y. Hsiao. P. Chung, W. T. Tsai, 2007, Baking treatment effect on materials characteristics and electrochemical behavior of anodic film formed on AZ91D magnesium alloy, Corros. Sci., Vol. 49, pp. 781-793 https://doi.org/10.1016/j.corsci.2006.05.045
  14. W. C. Oliver, G. M. Pharr, 1992, An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments, J. Mater. Res., Vol. 7, pp. 1564-1583 https://doi.org/10.1557/JMR.1992.1564
  15. H. Y. Hsiao, W. T. Tsai, 2005, Characterization of anodic films formed on AZ91D magnesium alloy, Surf. Coat. Technol., Vol. 190, pp. 299-308 https://doi.org/10.1016/j.surfcoat.2004.03.010
  16. A. K. Sharma, R. Uma Rani, M. Mayanna, 2001, Thermal studies on electrodeposited black oxide coating on magnesium alloys, Thermochimica Acta, Vol. 376, pp. 67-75 https://doi.org/10.1016/S0040-6031(01)00534-2
  17. N. Thangaraj, K. H. Westmacott, U. Dahmen, 1991, HVEM studied of the sintering of MgO nanoscystals prepared by $Mg(OH)_2$ decomposition, Ultramicroscopy, Vol. 37, pp. 362-374 https://doi.org/10.1016/0304-3991(91)90033-3
  18. M. Stern, A. L. Geary, 1957, Electrochemical polarization, J. Electrochem. Soc., Vol. 104, pp. 56-63 https://doi.org/10.1149/1.2428496
  19. H. Duan, K. Du, C. Yan, F. Wang, 2006, Electrochemical corrosion behavior of composite coatings of sealed MAO film on magnesium alloy AZ91D, Electrochim. Acta, Vol. 51, pp. 2898-2908 https://doi.org/10.1016/j.electacta.2005.08.026
  20. A. Ghasemi, V. S. Raja, C. Blawert, W. Dietzel, K. U. Kainer, 2008, Study of the structure and corrosion behavior of PEO coatings on AM50 magnesium alloy by electrochemical impedance spectroscopy, Surf. Coat. Technol., Vol. 202, pp. 3513-3518 https://doi.org/10.1016/j.surfcoat.2007.12.033