非等温回归再时效对Al-8Zn-2Mg-2Cu合金厚板组织及性能的影响

doi:10.11900/0412.1961.2017.00203

金属学报

2018, Vol. 54

Issue (1): 100-108 DOI: 10.11900/0412.1961.2017.00203

本期目录 | 过刊浏览

非等温回归再时效对Al-8Zn-2Mg-2Cu合金厚板组织及性能的影响

冯迪¹(

), 张新明², 陈洪美¹, 金云学¹, 王国迎¹

1 江苏科技大学材料科学与工程学院镇江 212003
2 中南大学材料科学与工程学院长沙 410083

Effect of Non-Isothermal Retrogression and Re-Ageing on Microstructure and Properties of Al-8Zn-2Mg-2Cu Alloy Thick Plate

Di FENG¹(

), Xinming ZHANG², Hongmei CHEN¹, Yunxue JIN¹, Guoying WANG¹

1 School of Materials Science and Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, China
2 School of Materials Science and Engineering, Central South University, Changsha 410083, China

引用本文:

冯迪, 张新明, 陈洪美, 金云学, 王国迎. 非等温回归再时效对Al-8Zn-2Mg-2Cu合金厚板组织及性能的影响[J]. 金属学报, 2018, 54(1): 100-108.
Di FENG, Xinming ZHANG, Hongmei CHEN, Yunxue JIN, Guoying WANG. Effect of Non-Isothermal Retrogression and Re-Ageing on Microstructure and Properties of Al-8Zn-2Mg-2Cu Alloy Thick Plate[J]. Acta Metall Sin, 2018, 54(1): 100-108.

全文: PDF(1026 KB) HTML

摘要:

基于铝合金厚板热处理时客观存在的非等温现象,利用非等温回归动力学模型、力学性能测试、电导率测试及TEM观察,研究了非等温回归温度场和时间的耦合效应对Al-8Zn-2Mg-2Cu (质量分数,%)合金厚板组织及性能的影响。结果表明,随着非等温回归时间的延长,合金的电导率逐渐升高,硬度和强度逐渐下降。优化的非等温回归再时效制度使MgZn₂相的尺寸分布范围宽化。因此,位错切过和位错绕过强化机制的合理匹配有效地降低了硬度的损失,同时合金的电导率得到显著提升。以105 ℃、24 h为预时效制度,经过慢速升温非等温回归处理120 min后再经120 ℃、24 h峰时效,Al-8Zn-2Mg-2Cu铝合金厚板的抗拉强度、屈服强度及电导率分别为620 MPa、593 MPa和21.1 MS/m,其综合性能优于单级峰时效(T6)及双级过时效(T73),且包含慢速升温的非等温回归再时效技术更适用于厚板的时效热处理。

关键词 ： Al-Zn-Mg-Cu合金, 厚板, 非等温回归再时效, 时效动力学

Abstract：

7000 series Al alloy has been widely used in aeronautical structural materials because of its high strength, high stress corrosion cracking resistance and good fatigue resistance when treated by retrogression and re-ageing (RRA). Al-8Zn-2Mg-2Cu (mass fraction, %) thick plate is supposed to manufacture the aircraft wing in Chinese big plane project. Due to the non-isothermal environment in the process of heat treatment for aluminum alloy thick plate, the influence of coupling effect of non-isothermal retrogression temperature field and time on the microstructure and properties of Al-8Zn-2Mg-2Cu alloy thick plate was investigated by the non-isothermal kinetic model, mechanical properties tests, electrical conductivity test and TEM observations. The results show that, the electrical conductivity increases while the hardness and strength decrease with the non-isothermal retrogression time increasing. The optimized non-isothermal retrogression and re-ageing (NRRA) treatment makes the size distribution range of MgZn₂ phase wider. Therefore,the logical matching between the dislocation cutting off mechanism and the dislocation by-passing mechanism effectively reduces the loss of hardness. Meanwhile, the electrical conductivity is significantly improved. After the treatment of 105 ℃, 24 h (pre-ageing) and non-isothermal regression (120 min) with slow heating rate and 120 ℃, 24 h re-ageing, the Al-8Zn-2Mg-2Cu alloy thick plate possesses an excellent comprehensive performance than those of T6 and T73 states. The tensile strength, yield strength and electrical conductivity are 620 MPa, 593 MPa and 21.1 MS/m, respectively. The NRRA treatment with slow heating rate is more suitable for the ageing treatment of thick plate.

Key words： Al-Zn-Mg-Cu alloy thick plate non-isothermal retrogression and re-ageing ageing kinetics

收稿日期: 2017-05-25

ZTFLH:

TG146.2

基金资助:国家重点基础研究发展计划项目No.2012CB619500,江苏省自然科学基金项目No.BK20160560,江苏省高校自然科学基金项目No.16KJB430010,江苏高校优势学科建设工程资助项目

作者简介:

作者简介冯迪,1984年生,博士

	服务

	把本文推荐给朋友
	加入引用管理器
	E-mail Alert
	RSS
	作者相关文章
	冯迪
	张新明
	陈洪美
	金云学
	王国迎
44.8K

链接本文:

https://www.ams.org.cn/CN/10.11900/0412.1961.2017.00203 或 https://www.ams.org.cn/CN/Y2018/V54/I1/100

图1 Al-8Zn-2Mg-2Cu合金(厚板)非等温回归示意图

表1 热处理工艺参数

图2 Al-8Zn-2Mg-2Cu合金30 mm厚板的时效温度曲线(回归阶段)

图3 不同时效状态下Al-8Zn-2Mg-2Cu合金30 mm厚板的硬度和电导率

图4 不同时效状态下Al-8Zn-2Mg-2Cu合金厚板的拉伸性能

图5 不同时效状态下Al-8Zn-2Mg-2Cu合金厚板晶内析出相的TEM明场像、SAED花样及衍射斑点示意图[19]

图6 不同时效状态下Al-8Zn-2Mg-2Cu合金厚板晶界析出相的TEM明场像

图7 Al-8Zn-2Mg-2Cu合金厚板中心层的Scheil积分-时间关系曲线

图8 不同时效状态下晶内析出相的尺寸分布统计图

[1]	Paul A R, Zhang Y, Knight S.Heat treatment of 7xxx series aluminium alloys—Some recent developments[J]. Trans. Nonferrous Met. Soc. China, 2014, 24: 2003
[2]	Zhang X M, Deng Y L, Zhang Y.Development of high strength aluminum alloys and processing techniques for the materials[J]. Acta Metall. Sin., 2015, 51: 257(张新明, 邓运来, 张勇. 高强铝合金的发展及其材料的制备加工技术[J]. 金属学报, 2015, 51: 257)
[3]	Grong ?, Shercliff H R.Microstructural modelling in metals processing[J]. Prog. Mater. Sci., 2002, 47: 163
[4]	Hutchinson C R, Gouné M, Redja?mia. A Selecting non-isothermal heat treatment schedules for precipitation hardening systems: An example of coupled process-property optimization[J]. Acta Mater., 2007, 55: 213
[5]	Jiang D M, Liu Y, Liang S, et al.The effects of non-isothermal aging on the strength and corrosion behavior of AlZnMgCu alloy[J]. J. Alloys Compd., 2016, 681: 57
[6]	Marlaud T, Deschamps A, Bley F, et al.Evolution of precipitate microstructures during the retrogression and re-ageing heat treatment of an Al-Zn-Mg-Cu alloy[J]. Acta Mater., 2010, 58: 4814
[7]	Staley J T.Method and process of non-isothermal aging for aluminum alloys [P]. Durham US Pat, 0237113Al, 2007
[8]	Li K, Zhang K, Yang L, et al.Investigation of non-isothermal aging process of 7085 aluminum alloy [A]. Proceedings of the 12th International Conference on Aluminium Alloys[C]. Yokohama: The Japan Institute of Light Metals, 2010: 2120
[9]	Zhen L, Huang M, Liu M, et al.Effect of cooling method on the microstructure and properties of 7085 aluminum alloy during non-isothermal aging [A]. Proceedings of the 12th International Conference on Aluminium Alloys[C]. Yokohama: The Japan Institute of Light Metals, 2010: 481
[10]	Jiang J T, Xiao W Q, Yang L, et al.Ageing behavior and stress corrosion cracking resistance of a non-isothermally aged Al-Zn-Mg-Cu alloy[J]. Mater. Sci. Eng., 2014, A605: 167
[11]	Liu Y, Jiang D M, Li B Q, et al.Effect of cooling aging on microstructure and mechanical properties of an Al-Zn-Mg-Cu alloy[J]. Mater. Des., 2014, 57: 79
[12]	Liu Y, Jiang D M, Li B Q, et al.Heating aging behavior of Al-8.35Zn-2.5Mg-2.25Cu alloy[J]. Mater. Des., 2014, 60: 116
[13]	Peng X Y, Guo Q, Liang X P, et al.Mechanical properties, corrosion behavior and microstructures of a non-isothermal ageing treated Al-Zn-Mg-Cu alloy[J]. Mater. Sci. Eng., 2017, A688: 146
[14]	Koziel J, Blaz L, Wloch G, et al.Precipitation processes during non-isothermal aging of fine-grained AA2219[J]. J. Alloys Compd., 2016, 682: 468
[15]	Cina B.Reducing the susceptibility of alloys, particularly aluminium alloys, to stress corrosion cracking [P].US Pat, 3856584, 1974
[16]	Feng D, Zhang X M, Liu S D, et al.The effect of pre-ageing temperature and retrogression heating rate on the microstructure and properties of AA7055[J]. Mater. Sci. Eng., 2013, A588: 34
[17]	Su R M, Qu Y D, Li D R.Pre-aging of retrogression and re-aging of spray formed 7075 alloy[J]. Acta Metall. Sin., 2014, 50: 863(苏睿明, 曲迎东, 李荣德. 喷射态7075合金回归再时效中预时效的研究[J]. 金属学报, 2014, 50: 863)
[18]	Starink M J, Li X M.A model for the electrical conductivity of peak-aged and overaged Al-Zn-Mg-Cu alloys[J]. Metall. Mater. Trans., 2003, 34A: 899
[19]	Chen J Z.Ageing precipitation behavior and mechanical properties of AA7055 aluminum alloy [D]. Harbin: Harbin Institute of Technology, 2008(陈军洲. AA7055 铝合金的时效析出行为与力学性能 [D]. 哈尔滨: 哈尔滨工业大学, 2008)
[20]	Feng D, Zhang X M, Liu S D, et al.Effect of pre-aging temperature and retrogression heating rate on microstructure and properties of 7150 alloy[J]. Chin. J. Nonferrous Met., 2013, 23: 1173(冯迪, 张新明, 刘胜胆等. 预时效温度及回归加热速率对7150铝合金显微组织及性能的影响[J]. 中国有色金属学报, 2013, 23: 1173)
[21]	Ning A L, Liu Z Y, Feng C, et al.Analysis on the behavior of exceeding peak aging strength of aluminum alloy at condition of retrogression and reaging[J]. Acta Metall. Sin., 2006, 42: 1253(宁爱林, 刘志义, 冯春等. 铝合金回归再时效状态的超峰时效强度行为分析[J]. 金属学报, 2006, 42: 1253)
[22]	Feng D, Zhang X M, Liu S D, et al.Non-isothermal retrogression kinetics for grain boundary precipitate of 7A55 aluminum alloy[J]. Trans. Nonferrous Met. Soc. China, 2014, 24: 2212
[23]	Feng D, Zhang X M, Liu S D, et al.Non-isothermal “retrogression and re-ageing” treatment schedule for AA7055 thick plate[J]. Mater. Des., 2014, 60: 208
[24]	Cui Z Q, Qin Y C.Metallography & Heat Treatment [M]. Beijing: Mechanical Industry Press, 2012: 179(崔忠圻, 覃耀春. 金属学与热处理 [M]. 北京: 机械工业出版社, 2012: 179)
[25]	Lumley R.Fundamentals of Aluminium Metallurgy [M]. London: Woodhead Publishing Ltd., 2011: 356
[26]	Cui X L, Wu Y Y, Zhang G J, et al.Study on the improvement of electrical conductivity and mechanical properties of low alloying electrical aluminum alloys[J]. Composites, 2017, 110B: 381
[27]	Zhang G Y, Zhang H, Fang G L, et al.Electronic structure of different regions and analysis of stress corrosion mechanism of Al-Zn-Mg-Cu alloys[J]. Acta Metall. Sin., 2009, 45: 687(张国英, 张辉, 方戈亮等. Al-Zn-Mg-Cu系铝合金中不同区域电子结构及应力腐蚀机理分析[J]. 金属学报, 2009, 45: 687)

[1]	王宗谱, 王卫国, Rohrer Gregory S, 陈松, 洪丽华, 林燕, 冯小铮, 任帅, 周邦新. 不同温度轧制Al-Zn-Mg-Cu合金再结晶后的{111}/{111}近奇异晶界[J]. 金属学报, 2023, 59(7): 947-960.
[2]	张守清, 胡小锋, 杜瑜宾, 姜海昌, 庞辉勇, 戎利建. 海洋平台用Ni-Cr-Mo-B超厚钢板的截面效应[J]. 金属学报, 2020, 56(9): 1227-1238.
[3]	程超,陈志勇,秦绪山,刘建荣,王清江. TA32钛合金厚板的微观组织、织构与力学性能[J]. 金属学报, 2020, 56(2): 193-202.
[4]	张正延,柴锋,罗小兵,陈刚,杨才福,苏航. 调质态含Cu高强钢的强化机理及钢中Cu的析出行为[J]. 金属学报, 2019, 55(6): 783-791.
[5]	马江南,王瑞珍,杨才福,查小琴,张利娟. 中厚板表层超细晶对止裂性能的影响[J]. 金属学报, 2017, 53(5): 549-558.
[6]	潘涛, 王小勇, 苏航, 杨才福. 合金元素Al对微B处理特厚钢板淬透性及力学性能的影响^*[J]. 金属学报, 2014, 50(4): 431-438.
[7]	刘胜胆李承波邓运来张新明. 时效对7055铝合金厚板淬透性的影响[J]. 金属学报, 2012, 48(3): 343-350.
[8]	张云崖邓运来万里张新明. 形变热处理对Al-Zn-Mg-Cu合金板材组织与硬度的影响[J]. 金属学报, 2011, 47(10): 1270-1276.
[9]	徐韦锋刘金合栾国红董春林. 厚板铝合金搅拌摩擦焊接头不同状态微观组织与力学性能[J]. 金属学报, 2009, 45(4): 490-496.
[10]	邓天勇吴迪许云波赵彦峰刘相华王国栋. 普碳钢中厚板热轧温度制定的一种新的数学方法[J]. 金属学报, 2009, 45(1): 67-72.
[11]	徐韦锋; 刘金合; 栾国红; 董春林 . 厚板铝合金搅拌摩擦焊接头显微组织与力学性能[J]. 金属学报, 2008, 44(11): 1404-1408 .
[12]	王洪斌; 崔华; 郝斌; 程军胜; 黄进峰; 张济山 . 喷射沉积超高强Al-Zn-Mg-Cu合金的回归再时效处理[J]. 金属学报, 2005, 41(12): 1267-1271 .
[13]	杨滨; 程军胜; 樊建中; 田晓风; 陈汉宾; 张济山 . 低温球磨纳米晶Al-Zn-Mg-Cu合金组织的演变[J]. 金属学报, 2005, 41(11): 1195-1198 .
[14]	张进之;李生智;王廷溥. 中厚板轧制稳定性条件的理论计算与实践验证[J]. 金属学报, 1992, 28(4): 68-72.

Viewed

Full text

Abstract

Cited

Shared

Discussed