Hot deformation behavior and microstructure evolution of 7075 aluminum alloy

doi:10.13251/j.issn.0254-6051.2023.06.027

Abstract

Abstract: Hot compression test was carried out for the as-solid solution treated 7075 aluminum alloy by MMS-100 thermo-mechanical simulator and the flow stress constitutive model of the alloy was constructed at 350-450 ℃ and strain rate among 0.01-10 s^-1. Based on the dynamic material model and microstructure, the optimum process window for the hot deformation was determined. The results show that after solution treatment at 475 ℃, the MgZn₂ phase is all dissolved back into the matrix, and with the increase of solution treatment time, the fraction of Al₂CuMg and Al₇Cu₂Fe dissolved in matrix increases. The flow stress of the alloy increases with the decrease of temperature and increase of strain rate, and the hot deformation activation energy calculated is approximately Q=153.724 kJ/mol. The power dissipation coefficient gradually increases with the temperature increasing and strain rate decreasing, the flow instability zones move to higher strain rate with the increase of strain, the optimum processing window of the alloy is deformation temperature of 420-450 ℃ and strain rate of 0.01-0.02 s^-1.

Key words: 7075 aluminum alloy, hot deformation, constitutive equation, processing map, microstructure evolution

CLC Number:

TG146.2⁺1

Li Chen, Wang Hebin, Ou Ping, Wang Hang, Wang Junfeng, Zhang Jishan. Hot deformation behavior and microstructure evolution of 7075 aluminum alloy[J]. Heat Treatment of Metals, 2023, 48(6): 147-156.

References

[1]张文沛, 李欢欢, 胡志力, 等. 车用轻量化铝合金材料本构关系研究进展[J]. 材料导报, 2017, 31(7): 85-89.
Zhang Wenpei, Li Huanhuan, Hu Zhili, et al. Progress in constitutive relationship research of aluminum alloy for automobile lightweighting[J]. Materials Reports, 2017, 31(7): 85-89.
[2]吴佳松, 蒋怡涵, 王武荣, 等. 7075铝合金板材热冲压成形中的高温摩擦[J]. 工程科学学报, 2020, 42(12): 1631-1638.
Wu Jiasong, Jiang Yihan, Wang Wurong, et al. High-temperature friction of 7075 aluminum alloy sheet during hot stamping[J]. Chinese Journal of Engineering, 2020, 42(12): 1631-1638.
[3]江海洋, 孙明月, 吴铭方, 等. 7075铝合金热变形连接接头的组织与性能[J]. 金属热处理, 2020, 45(2): 46-50.
Jiang Haiyang, Sun Mingyue, Wu Mingfang, et al. Microstructure and properties of 7075 aluminum alloy hot compress bonding joint[J]. Heat Treatment of Metals, 2020, 45(2): 46-50.
[4] Hu J L, Wu X J, Hong B, et al. Dislocation density model and microstructure of 7A85 aluminum alloy during thermal deformation[J]. Journal of Central South University, 2021, 28(10): 2999-3007.
[5]陶乐晓, 臧金鑫, 张坤, 等. 新型高强Al-Zn-Mg-Cu合金的热变形行为和热加工图[J]. 材料工程, 2013, 356(1): 16-20.
Tao Lexiao, Zang Jinxin, Zhang Kun, et al. Hot deformation behavior and processing map for new Al-Zn-Mg-Cu alloy[J]. Journal of Materials Engineering, 2013, 356(1): 16-20.
[6] Dai Q S, Deng Y L, Tang J G et al. Deformation characteristics and strain-compensated constitutive equation for AA5083 aluminum alloy under hot compression[J]. Transactions of Nonferrous Metals Society of China, 2019, 29(11): 2252-2261.
[7]吴凯, 韩维群, 张铁军, 等. 2A12铝合金的热压缩行为及热加工图[J]. 金属热处理, 2017, 42(4): 12-17.
Wu Kai, Han Weiqun, Zhang Tiejun, et al. Hot compression behavior and processing map of 2A12 aluminum alloy[J]. Heat Treatment of Metals, 2017, 42(4): 12-17.
[8]刘晓艳, 潘清林, 路聪阁, 等. 应力时效对Al-Cu-Mg-Ag耐热铝合金组织与性能的影响[J]. 航空材料学报, 2009, 29(3): 27-32.
Liu Xiaoyan, Pan Qinglin, Lu Congge, et al. Effects of external stress during aging on microstructure and properties of Al-Cu-Mg-Ag alloy[J]. Journal of Aeronautical Materials, 2009, 29(3): 27-32.
[9]叶拓, 何玉兵, 何文鹏, 等. 轧制态6082-T6铝合金的热压缩力学行为及微观组织分析[J]. 金属热处理, 2022, 47(2): 26-30.
Ye Tuo, He Yubing, He Wenpeng, et al. Hot compression behavior and microstructure analysis of as-rolled 6082-T6 aluminum alloy[J]. Heat Treatment of Metals, 2022, 47(2): 26-30.
[10]傅垒, 王宝雨, 林建国, 等. 耦合位错密度的6111铝合金热变形本构模型[J]. 北京科技大学学报, 2013, 35(10): 1333-1339.
Fu Lei, Wang Baoyu, Lin Jianguo, et al. Constitutive model coupled with dislocation density for hot deformation of 6111 aluminum alloy[J]. Journal of University of Science and Technology Beijing, 2013, 35(10): 1333-1339.
[11]刘萌, 李新亚, 臧勇, 等. 固溶成形工艺对6016铝合金组织及力学性能的影响[J]. 金属热处理, 2023, 48(2): 138-143.
Liu Meng, Li Xinya, Zang Yong, et al. Effect of solution forming process on microstructure and mechanical properties of 6016 aluminum alloy[J]. Heat Treatment of Metals, 2023, 48(2): 138-143.
[12]王冠, 田昌龄, 寇琳媛, 等. 6063铝合金双道次热变形微观组织演变[J]. 金属热处理, 2020, 45(5): 23-28.
Wang Guan, Tian Changling, Kou Linyuan, et al. Microstructure evolution of 6063 aluminum alloy during double-pass hot deformation alloy[J]. Heat Treatment of Metals, 2020, 45(5): 23-28.
[13] Guo L G, Yang S, Yang H, et al. Processing map of as-cast 7075 aluminum alloy for hot working[J]. Chinese Journal of Aeronautics, 2015, 28(6): 1774-1783.
[14]Parvizian F, Güzel A, Jger A, et al. Modeling of dynamic microstructure evolution of EN AW-6082 alloy during hot forward extrusion[J]. Computational Materials Science, 2011, 50(4): 1520-1525.
[15] Chen G, Lin F Y, Yao S J, et al. Constitutive behavior of aluminum alloy in a wide temperature range from warm to semi-solid regions[J]. Journal of Alloys and Compounds, 2016, 674: 26-36.
[16]罗锐, 曹赟, 邱宇, 等. 基于BP人工神经网络喷射成形7055铝合金的本构模型[J]. 航空材料学报, 2021, 41(1): 35-44.
Luo Rui, Cao Yun, Qiu Yu, et al. Investigation of constitutive model of as-extruded spray-forming 7055 aluminum alloy based on BP artificial neural network[J]. Journal of Aeronautical Materials, 2021, 41(1): 35-44.
[17]Zhang H, Li L X, Deng Y, et al. Hot deformation behavior of the new Al-Mg-Si-Cu aluminum alloy during compression at elevated temperatures[J]. Materials Characterization, 2007, 58(2): 168-173.
[18] Sellars C M, McTegart W J. On the mechanism of hot deformation[J]. Acta Metallurgica, 1966, 14(9): 1136-1138.
[19]刘伟, 吴远志, 邓彬, 等. 挤压态6061铝合金的力学性能及显微组织[J]. 金属热处理, 2020, 45(9): 172-177.
Liu Wei, Wu Yuanzhi, Deng Bin, et al. Mechanical properties and microstructure of extruded 6061 aluminum alloy[J]. Heat Treatment of Metals, 2020, 45(9): 172-177.
[20] Yan L M, Shen J, Li J P, et al. Deformation behavior and microstructure of an Al-Zn-Mg-Cu-Zr alloy during hot deformation[J]. International Journal of Minerals, Metallurgy and Materials, 2010, 17(1): 46-52.
[21] Chen B, Tian X L, Li X L, et al. Hot deformation behavior and processing maps of 2099 Al-Lialloy[J]. Journal of Materials Engineering and Performance, 2014, 23(6): 1929-1935.
[22]Morakabati M, Hajari A. Hot working behavior of near alpha titanium alloy analyzed by mechanical testing and processing map[J]. Transactions of Nonferrous Metals Society of China, 2020, 30(6): 1560-1573.
[23]Deng L, Zhang H D, Li G A, et al. Processing map and hot deformation behavior of squeeze cast 6082 aluminum alloy[J]. Transactions of Nonferrous Metals Society of China, 2022, 32(7): 2150-2163.
[24] Zhang T, Zhang S H, Li L, et al. Modified constitutive model and workability of 7055 aluminium alloy in hot plastic compression[J]. Journal of Central South University, 2019, 26(11): 2930-2942.
[25]Seshacharyulu T, Medeiros S C, Frazier W G, et al. Microstructural mechanisms during hot working of commercial grade Ti-6Al-4V with lamellar starting structure[J]. Materials Science and Engineering A, 2002, 325(1-2): 112-125.
[26]李展志, 李慧中, 王海军, 等. 6069铝合金的热变形行为和加工图[J]. 粉末冶金材料科学与工程, 2011, 16(2): 155-161.