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Study of Geometrically Necessary Dislocations of a Partially Recrystallized Aluminum Alloy Using 2D EBSD

Published online by Cambridge University Press:  10 April 2019

Majid Seyed Salehi Open the ORCID record for Majid Seyed Salehi [Opens in a new window] ,
Nozar Anjabin  and
Hyoung S. Kim
Majid Seyed Salehi*
Affiliation:
Department of Materials Science and Engineering, K. N. Toosi University of Technology, P.O. Box: 15875-4416, Tehran, Iran
Nozar Anjabin
Affiliation:
Department of Materials Science and Engineering, School of Engineering, Shiraz University, Zand Ave., Shiraz, Iran
Hyoung S. Kim
Affiliation:
Department of Materials Science and Engineering, Pohang University of Science and Technology, Pohang 37673, Republic of Korea
*
*Author for correspondence: Majid Seyed Salehi, E-mail: [email protected]
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Abstract

During recrystallization, the growth of fresh grains initiated within a deformed microstructure causes dramatic changes in the dislocation structure and density of a heavily deformed matrix. In this paper, the microstructure of a cold rolled and partially recrystallized Al-Mg alloy (AA5052) was studied via electron backscattered diffraction (EBSD) analysis. The structure and density of the geometrically necessary dislocations (GNDs) were predicted using a combination of continuum mechanics and dislocation theory. Accordingly, the Nye dislocation tensor, which determines the GND structure, was estimated by calculation of the lattice curvature. To do so, five components of the Nye dislocation tensor were directly calculated from the local orientation of surface points of the specimen, which was determined by two-dimensional EBSD. The remaining components of GNDs were determined by minimizing a normalized Hamiltonian equation based on dislocation energy. The results show the elimination of low angle boundaries, lattice curvature, and GNDs in recrystallized regions and the formation of low angle boundaries with orientation discontinuities in deformed grains, which may be due to static recovery.

Keywords

Electron backscatter diffractiongeometrically necessary dislocationsNye dislocation tensorpartially recrystallization
Type
Materials Applications
Information
Microscopy and Microanalysis , Volume 25 , Issue 3 , June 2019 , pp. 656 - 663
Copyright
Copyright © Microscopy Society of America 2019 

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References

Ashby, M (1970). The deformation of plastically non-homogeneous materials. Philos Mag 21(170), 399–424.10.1080/14786437008238426Google Scholar
Calcagnotto, M, Ponge, D, Demir, E & Raabe, D (2010). Orientation gradients and geometrically necessary dislocations in ultrafine grained dual-phase steels studied by 2D and 3D EBSD. Mater Sci Eng A 527(10), 2738–2746.Google Scholar
Chang, C & Duggan, B (2010). Relationships between rolled grain shape, deformation bands, microstructures and recrystallization textures in Al–5% Mg. Acta Mater 58(2), 476–489.Google Scholar
Demir, E, Raabe, D, Zaafarani, N & Zaefferer, S (2009). Investigation of the indentation size effect through the measurement of the geometrically necessary dislocations beneath small indents of different depths using EBSD tomography. Acta Mater 57(2), 559–569.Google Scholar
Engler, O & Randle, V (2009). Introduction to Texture Analysis: Macrotexture, Microtexture, and Orientation Mapping. New York: CRC Press.10.1201/9781420063660Google Scholar
Field, D, Merriman, C, Allain-Bonasso, N & Wagner, F (2012). Quantification of dislocation structure heterogeneity in deformed polycrystals by EBSD. Modell Simul Mater Sci Eng 20(2), 1–12.Google Scholar
Gupta, VK & Agnew, SR (2010). A simple algorithm to eliminate ambiguities in EBSD orientation map visualization and analyses: Application to fatigue crack-tips/wakes in aluminum alloys. Microsc Microanal 16(6), 831–841.10.1017/S1431927610093992Google Scholar
Hull, D & Bacon, DJ (2011). Introduction to Dislocations. Butterworth-Heinemann.Google Scholar
Humphreys, F (2001). Review grain and subgrain characterisation by electron backscatter diffraction. J Mater Sci 36(16), 3833–3854.Google Scholar
Kamaya, M, Wilkinson, AJ & Titchmarsh, JM (2005). Measurement of plastic strain of polycrystalline material by electron backscatter diffraction. Nucl Eng Des 235(6), 713–725.10.1016/j.nucengdes.2004.11.006Google Scholar
Karamched, PS & Wilkinson, AJ (2011). High resolution electron back-scatter diffraction analysis of thermally and mechanically induced strains near carbide inclusions in a superalloy. Acta Mater 59(1), 263–272.Google Scholar
Kysar, JW, Gan, YX, Morse, TL, Chen, X & Jones, ME (2007). High strain gradient plasticity associated with wedge indentation into face-centered cubic single crystals: Geometrically necessary dislocation densities. J Mech Phys Solids 55(7), 1554–1573.10.1016/j.jmps.2006.09.009Google Scholar
Liu, J & Morris, JG (2004). Recrystallization microstructures and textures in AA 5052 continuous cast and direct chill cast aluminum alloy. Mater Sci Eng A 385(1–2), 342–351.Google Scholar
Miyamoto, H, Ikeda, T, Uenoya, T, Vinogradov, A & Hashimoto, S (2011). Reversible nature of shear bands in copper single crystals subjected to iterative shear of ECAP in forward and reverse directions. Mater Sci Eng A 528(6), 2602–2609.10.1016/j.msea.2010.12.005Google Scholar
Nye, J (1953). Some geometrical relations in dislocated crystals. Acta Metall 1(2), 153–162.Google Scholar
Pantleon, W (2008). Resolving the geometrically necessary dislocation content by conventional electron backscattering diffraction. Scr Mater 58(11), 994–997.10.1016/j.scriptamat.2008.01.050Google Scholar
Rao, AU, Vasu, V, Govindaraju, M & Srinadh, KS (2014). Influence of cold rolling and annealing on the tensile properties of aluminum 7075 alloy. Procedia Mater Sci 5, 86–95.Google Scholar
Rao, SS (2009). Engineering Optimization: Theory and Practice. New Jersey: John Wiley & Sons.Google Scholar
Sun, S, Adams, B & King, W (2000). Observations of lattice curvature near the interface of a deformed aluminium bicrystal. Philos Mag A 80(1), 9–25.10.1080/01418610008212038Google Scholar
Tisza, M. (2013). Advanced materials for automotive application. In IOP Conf. Ser.: Mater. Sci. Eng., pp. 012010. IOP Publishing. doi:10.1088/1757-899X/47/1/012010.Google Scholar
Wang, S, Zhu, Z & Starink, M (2005). Estimation of dislocation densities in cold rolled Al-Mg-Cu-Mn alloys by combination of yield strength data, EBSD and strength models. J Microsc 217(2), 174–178.Google Scholar
Wilkinson, AJ & Randman, D (2010). Determination of elastic strain fields and geometrically necessary dislocation distributions near nanoindents using electron back scatter diffraction. Philos Mag 90(9), 1159–1177.Google Scholar
Wright, SI, Nowell, MM & Field, DP (2011). A review of strain analysis using electron backscatter diffraction. Microsc Microanal 17(3), 316–329.Google Scholar
Zhang, T, Jiang, J, Shollock, BA, Britton, TB & Dunne, FP (2015). Slip localization and fatigue crack nucleation near a non-metallic inclusion in polycrystalline nickel-based superalloy. Mater Sci Eng A 641, 328–339.10.1016/j.msea.2015.06.070Google Scholar