Statistical Analysis of Pit Dimensions for Pre-Corroded AA 7075-T6

Article Preview

Abstract:

Aluminum alloy 7075-T6 specimens were corroded in 3.5% NaCl solution for 120 hours and 240 hours, respectively. Morphology and dimensions of corrosion pits on specimen surface were inspected with white light confocal profiler. Statistical analysis shows that pit dimensions can be fitted well with log-normal and Gumbel distribution. After surface inspections, we performed high-cycle fatigue tests for the specimens. Fracture analysis shows that fatigue cracks initiate from single pit or two adjacent pits, and the crack-initiation pit shape and dimensions were examined with SEM. It is found that initiation pit dimensions can be well described with the log-normal distribution. Additionally, initiation pit dimensions are significantly larger than those measured on specimen surface before fatigue tests.

You might also be interested in these eBooks

Info:

Periodical:

Pages:

259-262

Citation:

Online since:

April 2014

Export:

Price:

Permissions CCC:

Permissions PLS:

Сopyright:

© 2014 Trans Tech Publications Ltd. All Rights Reserved

Share:

Citation:

* - Corresponding Author

[1] Z. Szklarska-Smmialowska, Pitting corrosion of aluminum, Corros. Sci. 41 (1999) 1743-1767.

Google Scholar

[2] G. T. Burstein, C. Liu, R. M. Souto, S. P. Vines, Origins of pitting corrosion, Corros. Eng. Sci. Technol. 39 (2004) 25-30.

Google Scholar

[3] Danfeng Zhang, Xiaoming Tan, Yueliang Chen, Distribution rule of corrosion damage morphology parameters for aluminum alloy, Proceedings of 2011 IEEE International Conference on Intelligence and Security Informatics, 358-361.

DOI: 10.1109/isi.2011.5984114

Google Scholar

[4] J.J. Medved, M. Breton, P.E. Irving, Corrosion pit size distributions and fatigue lives—a study of the EIFS technique for fatigue design in the presence of corrosion, Int. J. Fatigue 26 (2004) 71-80.

DOI: 10.1016/s0142-1123(03)00069-0

Google Scholar

[5] D. L. DuQuesnay, P. R. Underhill, H. J. Britt, Fatigue crack growth from corrosion damage in 7075-T6511 aluminium alloy under aircraft loading, Int. J. Fatigue 25 (2003) 371-377.

DOI: 10.1016/s0142-1123(02)00168-8

Google Scholar

[6] K. Jones, D. W. Hoeppner, Pit-to-crack transition in pre-corroded 7075-T6 aluminum alloy under cyclic loading, Corro. Sci. 47 (2005) 2185-2198.

DOI: 10.1016/j.corsci.2004.10.004

Google Scholar