7A41铝合金的力学性能和耐蚀性能

doi:10.13251/j.issn.0254-6051.2022.08.014

摘要/Abstract

摘要： 采用常温拉伸性能测试、应力腐蚀性能测试和盐雾腐蚀性能测试方法分别对双级时效态7A41铝合金的力学性能及耐蚀性能进行了测试。采用光学显微镜、扫描电镜(SEM)和透射电镜(TEM)对合金的显微组织、拉伸断口微观形貌进行了表征。结果表明,T6状态下合金的抗拉强度、屈服强度和伸长率分别为505 MPa、474 MPa和16.3%。耐应力腐蚀性能优异,应力腐蚀敏感系数为3.98%,合金的盐雾腐蚀速度为0.0914 mm/y。TEM观察分析表明,Tb态7A41铝合金晶内均匀弥散地分布着纳米级析出相,晶界上分布着大量的非连续析出相,析出相尺寸为20~50 nm,非连续析出相有效地阻碍了合金晶间腐蚀的路径,良好的组织特征保证了合金的综合性能。

关键词: 7A41铝合金, 力学性能, 应力腐蚀, 盐雾腐蚀

Abstract: Mechanical properties and corrosion resistance of the double-stage aged 7A41 aluminium alloy were tested by the test methods of tensile properties at room temperature, stress corrosion properties and salt spray corrosion properties, respectively. Microstructure of the alloy and the microscopic morphology of tensile fracture were characterized by metallographic microscope, scanning electron microscope(SEM) and transmission electron microscope(TEM). The results show that the tensile strength, yield strength and elongation of the alloy in T6 state are 505 MPa, 474 MPa and 16.3%, respectively. The stress corrosion resistance is excellent, the stress corrosion sensitivity coefficient is 3.98%, and the salt spray corrosion rate of the alloy is 0.0914 mm/y. TEM observation and analysis show that the nano-scale precipitates are uniformly dispersed in the double-stage aged 7A41 alloy grains, and a large number of discontinuous precipitates are distributed on the grain boundaries. The size of the precipitates is 20-50 nm. The discontinuous precipitates effectively hinder the path of intergranular corrosion of the alloy and the good microstructure characteristics ensure the comprehensive properties of the alloy.

Key words: 7A41 aluminium alloy, mechanical properties, stress corrosion, salt spray corrosion

中图分类号:

TG146.21

池海涛, 刘馥兵, 胡晓光. 7A41铝合金的力学性能和耐蚀性能[J]. 金属热处理, 2022, 47(8): 88-94.

Chi Haitao, Liu Fubing, Hu Xiaoguang. Mechanical properties and corrosion resistance of 7A41 aluminium alloy[J]. Heat Treatment of Metals, 2022, 47(8): 88-94.

参考文献

[1]Tolga D, Costas S. Recent developments in advanced aircraft aluminium alloys[J]. Materials and Design, 2014, 56: 862-871.
[2]叶拓, 唐明, 刘吉兆, 等. 固溶温度对 7075 铝合金板材组织与力学性能的影响[J]. 金属热处理, 2022, 47(3): 119-123.
Ye Tuo, Tang Ming, Liu Jizhao, et al. Effect of solution temperature on microstructure and mechanical properties of 7075 aluminum alloy sheet[J]. Heat Treatment of Metals, 2022, 47(3): 119-123.
[3]Tang J M, Shen Y F. Numerical simulation and experimental investigation of friction stir lap welding between aluminum alloys AA2024 and AA7075[J]. Journal of Alloys and Compounds, 2016, 665: 493-500.
[4]Williams J C, Starke Jr E A. Progress in structural materials for aerospace systems[J]. Acta Materialia, 2003, 51: 5775-5799.
[5]侯陇刚, 刘明荔, 王新东, 等. 高强7050铝合金超低温大变形加工与组织、性能调控[J]. 金属学报, 2017, 53(9): 1075-1090.
Hou Longgang, Liu Mingli, Wang Xindong, et al. Cryogenic processing high-strength 7050 aluminum alloy and controlling of the microstructures and mechanical properties[J]. Acta Metallurgica Sinica, 2017, 53(9): 1075-1090.
[6]Chen J F, Zhan X F, Zou L C, et al. Effect of precipitate state on the stress corrosion behavior of 7050 aluminum alloy[J]. Materials Characterization, 2016, 114: 1-8.
[7]孙燕, 任洁, 张艳姝. 固溶处理及双级时效对7050铝合金微观组织和硬度的影响[J]. 金属热处理, 2016, 41(3): 25-31.
Sun Yan, Ren Jie, Zhang Yanshu. Effects of solution and two-step aging on microstructure and hardness of 7050 aluminum alloy[J]. Heat Treatment of Metals, 2016, 41(3): 25-31.
[8]赵凤, 鲁法云, 郭富安. 7050铝合金双级时效制度的研究[J]. 金属热处理, 2015, 40(11): 149-153.
Zhao Feng, Lu Fayun, Guo Fuan. Two-step aging process of 7050 aluminum alloy[J]. Heat Treatment of Metals, 2015, 40(11): 149-153.
[9]丛福官, 赵刚, 田妮, 等. 7×××系超高强铝合金的强韧化研究进展及发展趋势[J]. 轻合金加工技术, 2012, 40(10): 23-33.
Cong Fuguan, Zhao Gang, Tian Ni, et al. Research progress and development trend of strengthening-toughening of ultra-high strength 7××× aluminum alloy[J]. Light Alloy Fabrication Technology, 2012, 40(10): 23-33.
[10]刘园. 高强耐蚀7050铝合金成分优化与时效行为研究[D]. 哈尔滨: 哈尔滨工业大学, 2016: 25-26.
Liu Yuan. Composition optimization and aging behaviour of high strength and corrosion resistance 7050 aluminum alloy[D]. Harbin: Harbin Institute of Technology, 2016: 25-26.
[11]Xiao Q F, Huan J W, Jiang Y G, et al. Effects of minor Sc and Zr additions on mechanical properties and microstructure evolution of Al-Zn-Mg-Cu alloys[J]. Transaction of Nonferrous Metals Society of China, 2020, 30: 1429-1438.
[12]刘丽敏. 高强钢在特高压输电塔中的应用[D]. 上海: 同济大学, 2007: 1-15.
Liu Limin. Application of high-intensity steel on electric transmission towers of ultra high voltage[D]. Shanghai: Tongji University, 2007: 1-15.
[13]尹飞, 杨璐, 施刚, 等. 高强度钢材钢结构抗震研究进展综述[J]. 钢结构, 2020, 35(3): 1-25.
Yin Fei, Yang Lu, Shi Gang, et al. Overview of research progress for seismic behavior of high strength steel struction[J]. Steel Construction, 2020, 35(3): 1-25.
[14]潘志军, 黎文献, 马正青, 等. 高强铝合金的研究现状及展望[J]. 铝加工, 2001, 24(4): 39-41.
Pan Zhijun, Li Wenxian, Ma Zhengqing, et al. Development and present stages of researching high strength aluminum alloys[J]. Aluminium Fabrication, 2001, 24(4): 39-41.
[15]Deschamps A, Brechet Y, Livet F. Influence of copper addition on precipitation kinetics and hardening in Al-Zn-Mg alloy[J]. Materials Science and Technology, 1999, 15(9): 993-1000.
[16]Meng Q J, Frankel G S. Effect of Cu content on corrosion behavior of 7××× series aluminum alloys[J]. Journal of the Electrochemical Society, 2004, 151(5): 271-283.
[17]Hadjadj L, Amira R. The effect of Cu addition on the precipitation and redissolution in Al-Zn-Mg alloy by the differential dilatometry[J]. Journal of Alloys and Compounds, 2009, 484: 891-895.
[18]Chinh N Q, Lendvai J, Ping D H, et al. The effect of Cu on mechanical and precipitation properties of Al-Zn-Mg alloys[J]. Journal of Alloys and Compounds, 2004, 378(1): 52-60.
[19]王少华. 高强铝合金的微合金化及热处理工艺研究[D]. 大连: 大连理工大学, 2011: 1-15.
Wang Shaohua. Study of microalloying and heat treatment proeess of high strength aluminum alloy[D]. Dalian: Dalian University of Technology, 2011: 1-15.
[20]曹艳艳, 黄甜甜, 韦春华, 等. 多向强应变-时效下7075合金组织、拉伸及抗晶间腐蚀性能[J]. 金属热处理, 2021, 46(6): 168-171.
Cao Yanyan, Huang Tiantian, Wei Chunhua, et al. Microstructure, tensile properties and intergranular corrosion resistance of 7075 aluminum alloy under multi-directional severe strain and aging[J]. Heat Treatment of Metals, 2021, 46(6): 168-171.
[21]丁轩, 甘玉荣, 蒋爱娟, 等. 时效处理对 7A55 铝合金微观组织和性能的影响[J]. 金属热处理, 2021, 46(9): 120-123.
Ding Xuan, Gan Yurong, Jiang Aijuan, et al. Influence of aging treatment on microstructure and properties of 7A55 aluminum alloy[J]. Heat Treatment of Metals, 2021, 46(9): 120-123.