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Effect of Fluoride Conversion Coating on the Corrosion Resistance and Adhesion of E-painted AZ31 Magnesium Alloy

  • Fazal, Basit Raza (Surface Technology Division, Korea Institute of Materials Science) ;
  • Moon, Sungmo (Surface Technology Division, Korea Institute of Materials Science)
  • Received : 2016.08.23
  • Accepted : 2016.10.14
  • Published : 2016.10.31

Abstract

This article reports improved corrosion resistance and adhesion of electro-paint (E-paint) with fluoride conversion coating (FCC) on AZ31 Mg alloy for the first time. These improvements were observed in comparison to chemically polished samples with no chemical conversion coating and samples with cerium conversion coatings (CeCC). FCCs were prepared in a hydrofluoric acid (HF) solution for four different times; 10, 30, 60, and 120 s. The colour of the samples changed from light gold to brown with increasing immersion time, indicating the formation of thicker FCC coatings with increasing immersion time. The adhesion of the E-paint on FCC-coated AZ31 Mg alloy was tested after 500 h of immersion in deionized (DI) water. Salt spray test (SST) results revealed delamination of E-paint on the chemically polished sample, severe blistering on the samples with CeCC, but no delamination and no blistering on the samples with FCC.

Keywords

References

  1. S. Verdier, N. van der Laak, S. Delalande, J. Metson, F. Dalard, The surface reactivity of a magnesium-aluminium alloy in acidic fluoride solutions studied by electrochemical techniques and XPS, Appl. Surf. Sci. 235 (2004) 513-524. https://doi.org/10.1016/j.apsusc.2004.03.250
  2. H. R. Bakhsheshi-Rad, M. H. Idris, M. R. A. Kadir, M. Daroonparvar, Effect of fluoride treatment on corrosion behavior of Mg-Ca binary alloy for implant application, Trans. Nonferrous Met. Soc. China. 23 (2013) 699-710. https://doi.org/10.1016/S1003-6326(13)62519-4
  3. T. F. da Conceicao, N. Scharnagl, C. Blawert, W. Dietzel, K. U. Kainer, Surface modification of magnesium alloy AZ31 by hydrofluoric acid treatment and its effect on the corrosion behaviour, Thin Solid Films. 518 (2010) 5209-5218. https://doi.org/10.1016/j.tsf.2010.04.114
  4. T. F. da Conceicao, N. Scharnagl, W. Dietzel, K. U. Kainer, Controlled degradation of a magnesium alloy in simulated body fluid using hydrofluoric acid treatment followed by polyacrylonitrile coating, Corros. Sci. 62 (2012) 83-89. https://doi.org/10.1016/j.corsci.2012.04.041
  5. T.F. da Conceicao, N. Scharnagl, W. Dietzel, K.U. Kainer, Corrosion protection of magnesium AZ31 alloy using poly(ether imide) [PEI] coatings prepared by the dip coating method: Influence of solvent and substrate pre-treatment, Corros. Sci. 53 (2011) 338-346. https://doi.org/10.1016/j.corsci.2010.09.040
  6. G. T. Bayer, M. Zamanzadeh, Failure analysis of paints and coatings, Publ. Internally Matco Assoc. SURFACE PREPARATION AND COATING APPLICATION PRACTICES. 331 (2004) 1-37.
  7. Y. Zheng, Magnesium Alloys as Degradable Biomaterials, CRC Press, (2015).
  8. T. S. N. S. Narayanan, I. S. Park, M. H. Lee, Surface Modification of Magnesium and its Alloys for Biomedical Applications: Modification and Coating Techniques, Elsevier, (2015).
  9. P. Y. Casanova, K. J. Jaimes, N. J. Parada, C. A. Hernandez-Barrios, M. Aparicio, F. Viejo, A. E. Coy, Synthesis and evaluation of $MgF_2$ coatings by chemical conversion on magnesium alloys for producing biodegradable orthopedic implants of temporary use, J. Phys. Conf. Ser. 466 (2013) 12003 1-4. https://doi.org/10.1088/1742-6596/466/1/012003
  10. X. -Y. Ye, M. -F. Chen, C. You, D. -B. Liu, The influence of HF treatment on corrosion resistance and in vitro biocompatibility of Mg-Zn-Zr alloy, Front. Mater. Sci. China. 4 (2010) 132-138. https://doi.org/10.1007/s11706-010-0025-0
  11. B. R. Fazal, S. Moon, Acid Pickling/polishing of AZ31 Magnesium Alloy, J. Korean Inst. Surf. Eng. 49 (2016) 231-237. https://doi.org/10.5695/JKISE.2016.49.3.231
  12. ASTM standard D3359-02, ASTM International 06.01 (2004) 1-8.
  13. ASTM standard B117-03, ASTM International 03.02 (2004) 1-12.
  14. T. Yan, L. Tan, B. Zhang, K. Yang, Fluoride Conversion Coating on Biodegradable AZ31B Magnesium Alloy, J. Mater. Sci. Technol. 30 (2014) 666-674. https://doi.org/10.1016/j.jmst.2013.12.015
  15. T. F. da Conceicao, N. Scharnagl, W. Dietzel, K. U. Kainer, Controlled degradation of a magnesium alloy in simulated body fluid using hydrofluoric acid treatment followed by polyacrylonitrile coating, Corros. Sci. 62 (2012) 83-89. https://doi.org/10.1016/j.corsci.2012.04.041
  16. T. F. da Conceicao, N. Scharnagl, W. Dietzel, D. Hoeche, K. U. Kainer, Study on the interface of PVDF coatings and HF-treated AZ31 magnesium alloy: Determination of interfacial interactions and reactions with self-healing properties, Corros. Sci. 53 (2011) 712-719. https://doi.org/10.1016/j.corsci.2010.11.001