Effect of the cyclic expansion-extrusion (CEE) process on mechanical properties and the grain refinement of AA6061 aluminum alloy
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https://doi.org/10.54939/1859-1043.j.mst.87.2023.100-107Keywords:
CEE; Aluminum alloy AA6061; Microhardness; Microstructure; UFGsAbstract
In this work, the cyclic expansion-extrusion (CEE) process for aluminum alloy AA6061 is due to its wide industrial applications. First, The CEE process is performed to create a fine stable grain size for the studied alloy. The microhardness of the deformed samples was determined to evaluate the effect of the CEE process on the mechanical properties of the alloy. The average microhardness of the deformed samples increased sharply after 1 CEE cycle from 40 Hv to 65 Hv or 68 Hv. It is particularly noticeable that in subsequent cycles, the average microhardness of the samples hardly changes (Hv ≈ 70). Subsequently, the microstructural survey was conducted to determine the average grain size of deformed samples. The average grain size reached about 5 ÷ 6 µm from the initial value of 100 μm after four CEE cycles. The results show that the effect of the cumulative strain of the CEEed samples significantly on the mechanical properties as well as for the grain refinement to create ultrafine grains (UFGs) in microstructures of the AA6061 alloy.
References
[1]. M. Besterci, T. Kvakaj, R. Kocisko, J. Bacso, K. Sulleiova, “Formation of UltraFine-Grained (UFG) structure and mechanical properties by severe plastic deformation (SPD)”, Metabk 47(4) 295-299, (2008).
[2]. R.Z. Valiev, R.K. Islamgaliev, I.V. Alexandrov, “Bulk nanostructured materials from severe plastic deformation”, Progress in Materials Science 45, pp. 103-189, (2000). DOI: https://doi.org/10.1016/S0079-6425(99)00007-9
[3]. Manh Tien Nguyen, Van Thao Le, Manh Hung Le, Truong An Nguyen, “Superplastic properties in a Ti5Al3Mo1.5 V titan alloy processed by multidirectional forging process”, Materials Letters 307, 131004, (2022). DOI: https://doi.org/10.1016/j.matlet.2021.131004
[4]. Valiev RZ, Langdon TG. “Principles of equal-channel angular pressing as a processing tool for grain refinement”, Prog Mater Sci 51, 881-981, (2006). DOI: https://doi.org/10.1016/j.pmatsci.2006.02.003
[5]. Megumi Kawasaki, Byungmin Ahn, HanJoo Lee, Alexander P. Zhilyaev and Terence G. Langdon, “Using high-pressure torsion to process an aluminum–magnesium nanocomposite through diffusion bonding”, Journal of Materials Research 33(1), (2016). DOI: https://doi.org/10.1557/jmr.2015.257
[6]. Natanael Geraldo Silva Almeida et al., Hardness, “Microstructure and Strain Distributions in Commercial Purity Aluminum Processed by Multi Directional Forging (MDF)”, Materials Research 23(4), (2020). DOI: https://doi.org/10.1590/1980-5373-mr-2020-0262
[7]. Juqiang Li, Juan Liu, Zhenshan Cui, “Microstructures and mechanical properties of AZ61 magnesium alloy after isothermal multidirectional forging with increasing strain rate”, Materials Science and Engineering: A 643, 32 - 36, (2015). DOI: https://doi.org/10.1016/j.msea.2015.07.028
[8]. Ting-Jian Zhang et al., “Structure and properties of multi-directionally forged 7075 aluminum alloy”, Rare Metal Materials and eEngineering 31(4), 257-260, (2002).
[9]. Hongzhi Fan et al., “Effects of cyclic expansion-extrusion with an asymmetrical extrusion cavity (CEE-AEC) on the microstructure and texture evolution of Mg-13Gd-4Y-2Zn-0.5Zr alloys”, Materials and Technology 54 (4), 495–501, (2020). DOI: https://doi.org/10.17222/mit.2019.251
[10]. N. Pardis, B. Talebanpour, R. Ebrahimi, and S. Zomorodian, “Cyclic expansion-extrusion (CEE): A modified counterpart of cyclic extrusion-compression (CEC)”, Materials Science and Engineering A 528, 7537-7540, (2011). DOI: https://doi.org/10.1016/j.msea.2011.06.059
[11]. Chang Xu et al., “The evolution of homogeneity and grain refinement during equal-channel angular pressing: A model for grain refinement in ECAP”, Materials Science and Engineering A 398(1-2), 66-76, (2005). DOI: https://doi.org/10.1016/j.msea.2005.03.083
[12]. Qing-feng Zhu et al., “Structure uniformity and limits of grain refinement of high purity aluminum during multi-directional forging process at room temperature”, Transactions of Nonferrous Metals Society of China 24(5), 1301-1306, (2014). DOI: https://doi.org/10.1016/S1003-6326(14)63192-7
