Journal of the Korean institute of surface engineering (한국표면공학회지)

The Korean Institute of Surface Engineering (한국표면공학회)
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Microstructural Analysis on Oxide Film of Al2024 Exposed to Atmospheric Conditions

대기 노출된 Al2024 알루미늄 합금 산화막에 대한 미세조직 분석

  • Kwon, Daeyeop (School of Mechanical Engineering, Pusan National University) ;
  • Choi, Wonjun (School of Mechanical Engineering, Pusan National University) ;
  • Bahn, Chi Bum (School of Mechanical Engineering, Pusan National University)
  • Received : 2021.02.06
  • Accepted : 2021.03.25
  • Published : 2021.04.30
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Abstract

Al2024 aluminum alloy specimens were exposed to atmospheric conditions for maximum 24 months and analyzed by electron microscopes to characterize their corrosion behavior and oxide film characteristics. As the exposure time increased from 12 months to 24 months, the number of pitting sites per 1 mm2 increased from ~100 to ~200. The uniform oxidation (or non-pitting) region of the 12-month exposure specimen showed 30~120 nm thick oxide layer, whereas the 24-month exposure specimen showed 170~200 nm thick oxide with the local oxygen penetration region up to 1 ㎛ deep. There was no local corrosion area observed in the 12-month exposure specimen except pitting. However, in the 24-month exposure specimen, local oxygen penetration region was observed beneath the uniform oxide layer and near the pitting cavity. Al2024 showed two times thicker uniform oxide layer but much shallower local oxygen penetration region than Al1050, which appears to be related to low Si concentration. Further research is needed on the effects of Mg segregation near the tip of the oxygen penetration region.

Keywords

Acknowledgement

이 논문은 부산대학교 기본연구지원사업(2년)에 의하여 연구되었음.

References

  1. ASM International, ASM Handbook Vol 13A Corrosion: Fundamentals, Testing, and Protection, 2003, pp. 196-209.
  2. N. D. Alexopoulos, C. J. Dalakouras, P. Skarvelis, S. K. Kourkoulis, Accelerated corrosion exposure in ultra thin sheets of 2024 aircraft aluminum alloy for GLARE applications, Corro. Sci. 55 (2012) 289-300. https://doi.org/10.1016/j.corsci.2011.10.032
  3. S. Sun, Q. Zheng, D. Li, J. Wen, Long-term atmospheric corrosion behaviour of aluminium alloys 2024 and 7075 in urban, coastal and industrial environments, Corros. Sci. 51 (2009) 719-727. https://doi.org/10.1016/j.corsci.2009.01.016
  4. B. B. Wang, Z. Y. Wang, W. Han, W. Ke, Atmospheric corrosion of aluminum alloy 2024-T3 exposed to salt lake environment in Western China, Corros. Sci. 59 (2012) 63-70. https://doi.org/10.1016/j.corsci.2012.02.015
  5. S. Sun, S. Chen, Y. Ma, Q. Zheng, S. Hu, Exfoliation Corrosion of Extruded AA2024-T4 in the Industrial and Coastal-Industrial Environment, Corrosion 70 (2014) 1064-1073.
  6. T. Zhang, Y. He, R. Cui, T. An, Long-Term Atmospheric Corrosion of Aluminum Alloy 2024-T4 in a Coastal Environment, J. Mater. Eng. Perform. 24 (2015) 2764-2773. https://doi.org/10.1007/s11665-015-1541-y
  7. S. Zhang, T. Zhang, Y. He, D. Liu, J. Wang, X. Du, B. Ma, Long-term atmospheric corrosion of aluminum alloy 2024-T4 in coastal environment: Surface and sectional corrosion behavior, J. Alloys Comp. 789 (2019) 460-471. https://doi.org/10.1016/j.jallcom.2019.03.028
  8. T. F. Otero, A. Porro, A. S. Elola, Prediction of Pitting Probability on 1050 Aluminum in Environmental Conditions, Corrosion 48 (1992) 785-791. https://doi.org/10.5006/1.3316000
  9. X. K. Yang, L. W. Zhang, S. Y. Zhang, M. Liu, K. Zhou, X. L. Mu, Properties degradation and atmospheric corrosion mechanism of 6061 aluminum alloy in industrial and marine atmosphere environments, Mater. Corros. 68 (2017) 529-535. https://doi.org/10.1002/maco.201609201
  10. M. Poltavtseva, A. Heyn, E. Boese, Long term corrosion behavior of clad aluminum materials under different atmospheric conditions, Mater. Corros. 64 (2013) 723-730. https://doi.org/10.1002/maco.201206962
  11. J. Ryl, J. Wysocka, M. Jarzynka, A. Zielinski, J. Orlikowski, K. Darowicki, Effect of native air-formed oxidation on the corrosion behavior of AA 7075 aluminum alloys, Corros. Sci. 87 (2014) 150-155. https://doi.org/10.1016/j.corsci.2014.06.022
  12. S.P. Knight, M. Salagaras, A.R. Trueman, The study of intergranular corrosion in aircraft aluminium alloys using X-ray tomography, Corros. Sci. 53 (2011) 727-734. https://doi.org/10.1016/j.corsci.2010.11.005
  13. Yoshiyuki Oya, Yoichi Kojima, Nobuyoshi Hara, Influence of Silicon on Intergranular Corrosion for Aluminum Alloys, MATERIALS TRANSACTIONS, Volume 54, Issue 7, (2013), 1200-1208. https://doi.org/10.2320/matertrans.M2013048
  14. Binger, W. W., Hollingsworth, E. H. and Sprawls, D., In Aluminium Vol. I, ed. Van Horn, ASM, (1967), p. 209.
  15. M. Kaifu, H. Fujimoto and M. Takemoto, Influence of Mn contents and heat treatments on intergranular corrosion of Al-Mn alloys, J. Japan Inst. Met. 32 (1982), 135-142.
  16. M. Zamin, The Role of Mn in the Corrosion Behavior of Al-Mn Alloys, Corrosion 37 (1981) 627-632. https://doi.org/10.5006/1.3577549
  17. Y. Zheng, B. Luo, Z. Bai, J. Wang, and Y. Yin, Study of the Precipitation Hardening Behavior and Intergranular Corrosion of Al-Mg-Si Alloys with Differing Si Contents, Metals 7(10), (2017) 387. https://doi.org/10.3390/met7100387
  18. J. R. Galvele and S. M. de De Micheli, Mechanism of intergranular corrosion of Al-Cu alloys, Corros. Sci. 10 (1970), 795-807. https://doi.org/10.1016/S0010-938X(70)80003-8
  19. Y. Zou, Q. Liu, Z. Jia, Y. Xing, L. Ding, and X. Wang, The intergranular corrosion behavior of 6000-series alloys with different Mg/Si and Cu content, Appl. Surf. Sci. 405 (2017) 489-496. https://doi.org/10.1016/j.apsusc.2017.02.045
  20. Y. S. Kim, H. K. Lim, J. J. Kim, W. S. Hwang, and Y. S. Park, Corrosion cost and corrosion map of Korea-Based on the data from 2005 to 2010, Corros. Sci. Tech. 10 (2011) 52-59. https://doi.org/10.14773/CST.2011.10.2.052
  21. 김선규, 이찬형, 반치범. 대기 부식에 의해 생성된 Al1050 및 Al7075 알루미늄 합금 산화막에 대한 투과전자현미경 분석. 한국표면공학회지, 50(6), (2017) 447-454. https://doi.org/10.5695/JKISE.2017.50.6.447
  22. 김대건, 김가림, 최원준, 반치범, 24개월 대기 노출된 Al1050 및 Al7075 알루미늄 합금 산화막에 대한 투과전자현미경 분석. 한국표면공학회지, 52(2), (2019) 62-71. https://doi.org/10.5695/JKISE.2019.52.2.62
  23. American Society for Testing and Materials (ASTM) International, ASTM G50-10 Standard Practice for Conducting Atmospheric Corrosion Tests on Metals (2010).
  24. Z. Cui, X. Li, H.ZhangK.XiaoC.Dong, Z.Liu,L.Wang, Atmospheric corrosion behavior of 2A12 aluminum alloy in a tropical marine environment, Advances Mater. Sci. Eng. (2015) Article ID 163205.