Quantitative Measurement of Strain Field around η′ Phase in a 7000 Series Aluminum Alloy

Abstract:

The strain field of η′ phase in an aged 7000 series aluminum alloy has been investigated using a combination of high resolution transmission electron microscopy (HRTEM) and geometric phase analysis (GPA) technique in this paper, and strain components ε_xx, ε_yy were mapped, respectively. The results showed that the strain is mainly generated near the matrix/η′ phase interface and gradually decreases with distance increasing away from the interface. There were convergence and divergence regions of the strain within the η′ phase, and maximum strain occurred in the position where about 0.25 nm far from the interface, value of the maximum strains was about 2.54%.

• Periodical: Materials Science Forum (Volume 877)
• Pages: 200-204
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.877.200
• Online since: November 2016
• Authors: Fei Liu, Pu Cun Bai*, Xiao Hu Hou, Yong Ming Xing
• Keywords: Aluminium Alloy, Geometric Phase Analysis, High-Resolution Transmission Electron Microscopy, Strain Field

References

[1] A. Heinz, A. Haszler, C. Keidel, S. Moldenhauer, R. Benedictus, WS. Miller, Recent development in aluminum alloys for aerospace applications, Mater. Sci. Eng. A. 280 (2000) 102-107.

DOI: 10.1016/s0921-5093(99)00674-7

[2] D. Wang, D.R. Ni, Z.Y. Ma, Effect of pre-strain and two-step aging on microstructure and stress corrosion cracking of 7050 alloy, Mater. Sci. Eng. A. 494 (2008) 360-366.

DOI: 10.1016/j.msea.2008.04.023

[3] P. C. Bai, X. H. Hou, X. Y. Zhang, C. W. Zhao, Y. M. Xing, Microstructure and mechanical properties of a large billet of spray formed Al–Zn–Mg–Cu alloy with high Zn content, Mater. Sci. Eng. A. 508(2009) 23-27.

DOI: 10.1016/j.msea.2008.12.010

[4] S. P. Ringer, K. Hono, Microstructural evolution and age hardening in aluminium alloys: atom probe field-ion microscopy and transmission electron microscopy studies, Materials Characterization. 44(2004) 101-131.

DOI: 10.1016/s1044-5803(99)00051-0

[5] V. Hansen, O. B. Karlsen, Y. Langsrud, Precipitates, zones and transitions during aging of Al-Zn-Mg-Zr 7000 series alloy, Materials Science and Technology. 20(2004) 185-193.

DOI: 10.1179/026708304225010424

[6] D. Dumont, A. Deschamps, Y. Brechet, On the relationship between microstructure, strength and toughness in AA7050 aluminum alloy, Mater. Sci. Eng. A. 356 (2003) 326-336.

DOI: 10.1016/s0921-5093(03)00145-x

[7] M. J. Hÿtch, T. lamann, Imaging conditions for reliable measurement of displacement and strain in high-resolution electron microscopy, Ultramicroscopy. 87(2001) 199-212.

DOI: 10.1016/s0304-3991(00)00099-1

[8] M. J. Hÿtch, E. Snoeck, R. Kilaas, Imaging conditions for reliable measurement of displacement and strain in high-resolution electron microscopy, Ultramicroscopy. 74 (1998) 131-146.

DOI: 10.1016/s0304-3991(98)00035-7

[9] M. J. Hÿtch, J. L. Putaux, J. M. Pénisson, Measurement of the displacement field of dislocations to 0. 03Å by electron microscopy, Nature. 423(2003) 270-273.

DOI: 10.1038/nature01638

[10] J. L. Taraci, M. J. Hÿtch, T. Clement, P. Peralta, M.R. McCartney, Jeff Drucker, et al., Strain mapping in nanowires, Nanotechnology. 16 (2005) 2365.

DOI: 10.1088/0957-4484/16/10/062

[11] Z. W. Liu, H. M. Xie, D. N. Fang, F. L. Dai, Q. K. Xue, H. Liu, J. F. Jia, Residual strain around a step edge of artificial Al ∕Si (111) - 7 × 7 nanocluster, Appl Phys Lett. 87(2005) 201908.

DOI: 10.1063/1.2130722

[12] Q. H. Wang, H. M. Xie, Z. W. Liu, X. H. Lou, J. F. Wang, K. W. Xu, Z. H. Zhang, J. H. Liao, C. Z. Gu. Residual stress assessment of interconnects by slot milling with FIB and geometric phase analysis, Opt Laser Eng. 48(2010) 1113-1118.

DOI: 10.1016/j.optlaseng.2009.12.006