Effect of pre-aging treatment on hardening response and microstructure of Al-Zn-Mg-Cu alloy

doi:10.13251/j.issn.0254-6051.2020.07.019

Abstract

Abstract: Effect of pre-aging treatment on mechanical properties and microstructure of Al-Zn-Mg-Cu aluminum alloy was investigated. The micro-hardness and mechanical properties were tested. The microstructure was characterized. The results indicate that the best pre-aging hardening effect of the experimental Al-Zn-Mg-Cu aluminum alloy is achieved while aging at 180 ℃ immediately after solution treatment, during which the peak value reaches 195 HV0.5 and the main hardening phase is η′ phase. The optimal pre-aging treatment is under 120 ℃×10 min. Thus, after 14 days natural aging, the hardness of the alloy is decreased by 13 HV0.5 or 10.7% compared to the solution+natural aging treatment. Finally after bake hardening process, the yield strength and tensile strength of the pre-aged alloy reach 465 MPa and 545 MPa, showing a hardening increase of 170 MPa and 95 MPa,respectively, and the elongation reaches 12.5%.

Key words: Al-Zn-Mg-Cu aluminum alloy, mechanical properties, pre-aging treatment, microstructure

CLC Number:

TG156.1

Wei Maoyuan, Wang Hongzhen, Zhang Hong, Teng Dunbo. Effect of pre-aging treatment on hardening response and microstructure of Al-Zn-Mg-Cu alloy[J]. Heat Treatment of Metals, 2020, 45(7): 90-93.

References

[1]陈辉, 景财年. 热成形技术在汽车轻量化中的应用与发展[J]. 金属热处理, 2016, 41(3): 61-66.
Chen Hui, Jing Cainian. Application and development of hot forming technology for automobile lightening[J]. Heat Treatment of Metals, 2016, 41(3): 61-66.
[2]Miller W S, Zhuang L, Bottema J, et al. Recent development in aluminum alloys for the automotive industry[J]. Materials Science and Engineering A, 2000, 280(1): 37-49.
[3]Hirsch J. Recent development in aluminum for automotive applications[J]. Transactions of Nonferrous Metals Society of China, 2014, 24(7): 1995-2002.
[4]Henriksson F, Johansen K. On material substitution in automotive BIWs-from steel to aluminum body sides[J]. Procedia CIRP, 2016, 50: 683-688.
[5]Heina A, Haszler A, Keidel C, et al. Recent development in aluminium alloys for aerospace applications[J]. Materials Science and Engineering A, 2000, 280(1): 102-107.
[6]Dursun T, Soutis C. Recent developments in advanced aircraft aluminum alloys[J]. Materials and Design, 2014, 56: 862-871.
[7]Jiang F L, Zurob H S, Purdy G R, et al. Characterizing precipitate evolution of an Al-Zn-Mg-Cu based commercial alloy during artificial aging and non-isothermal heat treatments by in situ electrical resistivity monitoring[J]. Materials Characterization, 2016, 117: 47-56.
[8]Ozer G, Karaaslan Ahmet. Properties of AA7075 aluminum alloy in aging and retrogression and reaging process[J]. Transactions of Nonferrous Metals Society of China, 2017, 27(11): 2357-2362.
[9]Ghiaasiaan R, Amirkhiz B S, Shankar S. Quantitative metallography of precipitating and secondary phases after strengthening treatment of net shaped casting of Al-Zn-Mg-Cu (7000) alloys[J]. Materials Science and Engineering A, 2017, 698: 206-217.
[10]王小娜, 韩利战, 顾剑锋. 铝合金时效析出动力学及强化模型[J]. 中国有色金属学报, 2013, 23(10): 2754-2768.
Wang Xiaona, Han Lizhan, Gu Jianfeng. Aging precipitation kinetics and strengthening models for aluminum alloys[J]. The Chinese Journal of Nonferrous Metals, 2013, 23(10): 2754-2768.
[11]刘秋平, 刘志勇, 赵俊, 等. Zn含量及回归热处理对7075铝合金性能的影响[J]. 金属热处理, 2016, 41(2): 11-15.
Liu Qiuping, Liu Zhiyong, Zhao Jun, et al. Effect of Zn content and retrogression and re-aging treatment on properties of 7075 aluminum alloy[J]. Heat Treatment of Metals, 2016, 41(2): 11-15.

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