METALS AND METAL MATRIX COMPOSITES |
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Study on Hot Deformation Behavior and Microstructure Evolution Mechanism of AA7021 Aluminum Alloy |
QIU Peng, WANG Jiayi, DUAN Xiaoge, LIN Hongtao, CHEN Kang, JIANG Haitao
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Institute of Engineering and Technology, University of Science and Technology Beijing, Beijing 100083, China |
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Abstract Athermal compression experiment for AA7021 aluminum under a temperature ranging from 350—490 ℃ and a strain rate ranging from 0.01—10 s-1 was carried out by using gleeble-3500 thermal simulation test machine. A strain-based constitutive equation and a thermal processing diagram of the thermal deformation characteristic of the material was established and the microstructure of the safety zone and the instability zone in the thermal processing diagram was analyzed. The results show that the deformation induced precipitation effect is found in the safety zone. In the deformation instability zone, when the deformation temperature became lower and strain rate became high, the adiabatic shear zone is formed due to the effect of strain heat. In addition, in the region where the strain rate is greater than 1 s-1, the cause of deterioration of aluminum hot workability are found to be local rheology, large particle breakage, microcrack, etc. During the thermal deformation process, the dynamic softe-ning mechanism of aluminum changes from dynamic recovery to dynamic recrystallization as the temperature increase. AA7021 aluminum alloy coexists a variety of softening mechanism in the medium temperature and high temperature compression process, but dynamic recovery still dominates.
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Published: 25 April 2020
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Fund:This work was financially supported by the Science and Technology Major Project of Guangxi (Guike AA17202008-2). |
About author:: Peng Qiu, graduate student of University of Science and Technology Beijing(USTB), obtained a bachelor’s degree in material forming and control engineering from Yantai Nanshan College in September 2013 to July 2017.He has been studying for a master’s degree at University of Science and Technology Beijing(USTB) since 2017.The research work mainly focuses on the research and development of aluminum alloy automotive panels. Haitao Jiang, as a professor and Doctoral Tutor in University of Science and Technology Beijing (USTB). He mainly engaged in the development of steel and non-ferrous metal materials and the study of strip production technology. He has a dozen programs of NSFC(Natural Science Foundation of China), National Key Research and Development Plan and the Beijing municipal scie-nce and technology plan projects. He has also published over two hundred academic papers and received many authorized patents and received the first prize of two provincial and mi-nisterial levels so far. |
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1 Miller W S, Zhuang L, Bottema J, et al. Material Science and Enginee-ring A, 2000, 280(l), 37. 2 Sakural T. Kobelco Technology Review, 2006, 28(28), 22. 3 Wang Y G, Study of formability properties of 5182 aluminum alloy automobile plate. Master’s Thesis, Chongqing University, China, 2016(in Chinese). 王游根. 5182铝合金汽车板成形性能的研究. 硕士学位论文, 重庆大学, 2016. 4 Fu J, Qi W J, Li Y, et al. Materials Research and Application, 2016, 10(3), 3(in Chinese). 付锦, 戚文军, 李亚军, 等. 材料研究与应用, 2016, 10(3), 3. 5 Barberis Pinlung S. 7xxx aluminum sheets for automotive applications. Master Theses, University of Windsor, 2015. 6 Dai Q S, Ou S S, Deng Y L, et al.Materials Review B: Research Papers, 2017, 31(7), 7(in Chinese). 戴青松, 欧世声, 邓运来, 等. 材料导报: 研究篇, 2017, 31(7), 7. 7 Huang C Q, Diao J P, Deng H, et al. Transactions of Nonferrous Metals Society of China, 2013(6), 1576(in Chinese). 黄长清, 刁金鹏, 邓华, 等.中国有色金属学报, 2013(6), 1576. 8 Li D F, Zhang D Z, Liu D S, et al. Transactions of Nonferrous Metals Society of China, 2016, 26(6), 1491(in Chinese). 李东锋, 张端正, 刘胜胆, 等. 中国有色金属学报, 2016, 26(6), 1491. 9 Chen S Y, Chen K H, Jia L, et al.Transactions of Nonferrous Metals Society of China, 2013, 23(2), 329(in Chinese). 陈宋义, 陈康华, 贾乐, 等. 中国有色金属学报, 2013, 23(2), 329. 10 Roboson J D, Prangnell P B.Material Science and Technology, 2002, 18(6), 607. 11 Fu L, Wang B Y, Zhou J, et al. Journal of Plasticity Engineering, 2013, 20(2), 107. 12 Prasad Y V R K, Gegel H L, Doraivelu S M. Metallurgical transactions, 1984, 15(10), 1883. 13 Prasad Y V R K. Journal of Materials Engineering and performance, 2003, 12(6), 638. 14 Ramanathan S, Karthikeyan R, Gupta M.Journal of Materials Processing Technology, 2007, 183(1), 104. 15 Venugopal S, Venugopal P, Mannan S L. Journal of Materials Processing Technology, 2008, 202(1-3), 201. 16 Frost H J, Ashby M F. Deformation mechanism maps: the plasticity and creep of metals and ceramics. Pergamon press, UK, 1982. 17 Hao A G, Ji W, Hao H L.Hot Working Technology, 2018, 47(17), 141(in Chinese). 郝爱国, 吉卫, 郝花蕾. 热加工工艺, 2018, 47(17), 141. 18 Wang X X, Zhang X, Wang H D, et al. Special Casting & Nonferrous Alloys, 2017, 37(9), 944(in Chinese). 王晓溪, 张翔, 王华东, 等. 特种铸造及有色合金, 2017, 37(9), 944. 19 Robinson J S, Tanner D A, Truman C E, et al.Material Characterization, 2012, 65, 73. 20 Liu S, Zhong Q, Zhang Y, et al.Material & Design, 2013, 31(6), 3116. 21 Davies R K, Randle V, Marshall.Acta Materialia, 1998, 46(17), 6021. 22 Humphreys F J. Acta Metallurgica, 1977, 25(11), 1323. 23 Taylor G. Progress in materials science, 1992, 36, 29. 24 Rao K P, Prasad Y. Journal of Mechanical Working Technology, 1986, 13(1), 83. 25 Humphreys F J, Hatherly M. Recrystallization and related annealing phenomena. Elsevier, UK, 2012. 26 Gourdet S, Montheillet F. Material Science & Engineering A, 2000, 283(l), 274. 27 Shimizu I. Journal of Structural Geology, 2008, 30(7), 89. |
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