Journal of Central South University

, Volume 25, Issue 5, pp 961–975 | Cite as

Effect of annealing treatment on microstructure and fatigue crack growth behavior of Al–Zn–Mg–Sc–Zr alloy

  • Jing Chen (陈婧)
  • Qing-lin Pan (潘清林)
  • Xue-hong Yu (虞学红)
  • Meng-jia Li (李梦佳)
  • Hao Zou (邹浩)
  • Hao Xiang (向浩)
  • Zhi-qi Huang (黄志其)
  • Quan Hu (胡权)


Al–Zn–Mg–Sc–Zr alloy samples were annealed to four different states (under-aging, peak-aging, over-aging and double-aging) and then thoroughly investigated by means of electron backscatter diffraction (EBSD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), tensile and fatigue crack growth rate tests to explore the influence of annealing treatment on microstructure and fatigue crack growth behavior. The results indicate that Al3(Sc,Zr) particles can effectively refine grains and enhance tensile properties and fatigue properties. After annealing treatment, the under-aged sample and double-aged sample obtained average grain sizes of 4.9473 and 4.1257 μm, and the maximum value of yield/tensile strength (561 MPa/581 MPa) was obtained in peak-aged state. In the Paris region, fatigue crack growth rate, crack deflection and bifurcation, crack blunting and inter/trans-granular propagation were discussed based on data fitting and Laird model and Griffith theory. And the results show that the under-aged sample possesses the best resistance to fatigue crack propagation and the most tortuous and bifurcated crack path. For all samples, the fatigue crack growth rate in the rupture region was inversely proportional to yield strength.

Key words

Al–Zn–Mg–Sc–Zr alloy annealing treatment microstructures fatigue crack growth rate fatigue crack path 

热处理对Al–Zn–Mg–Sc–Zr 合金的显微结构及疲劳裂纹扩展行为的影响


本文采用电子背散射衍射(EBSD)、透射电子显微分析(TEM)、扫描电子显微分析(SEM)、 室温拉伸性能测试和疲劳裂纹扩展测试的方法研究了4 种时效处理(欠时效、峰时效、过时效和双级 时效)对Al–Zn–Mg-Sc–Zr 合金的显微组织和疲劳裂纹扩展行为的影响。 结果表明:合金中的Al3(Sc,Zr) 粒子能显著地细化合金晶粒、提升拉伸性能和抗疲劳裂纹扩展性能。其中,欠时效样品和双级时效样 品的平均晶粒尺寸分别为4.9473 μm 和4.1257 μm,峰时效处理后样品达到最高的屈服强度和抗拉强 度(561 MPa 和581 MPa)。基于Laird 模型和 Griffith 理论,本文研究了合金在Paris 区域中的裂纹 扩展速率、裂纹曲折与分叉、裂纹钝化与裂纹的沿晶和穿晶扩展行为。结果表明,欠时效样品表现出 最佳的抗疲劳裂纹扩展性能,其裂纹路径最为曲折、裂纹分叉最多。在高速扩展区域中,所有样品的 疲劳裂纹扩展速率均和屈服强度负相关。


Al–Zn–Mg–Sc–Zr 合金 热处理 显微组织 疲劳裂纹扩展速率 疲劳裂纹扩展路径 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. [1]
    ZHANG Li-hua, YU Jun, ZHANG Xiao-ming. Effect of ultrasonic power and casting speed on solidification structure of 7050 aluminum alloy ingot in ultrasonic field [J]. Journal of Central South University of Technology, 2010, 17: 431–436.CrossRefGoogle Scholar
  2. [2]
    WILLIAMS J C, STARKE E A. Progress in structural materials for aerospace systems [J]. Acta Materialia, 2003, 51(19): 5775–5799.CrossRefGoogle Scholar
  3. [3]
    DURSUN T, SOUTIS C. Recent developments in advanced aircraft aluminium alloys [J]. Materials & Design, 2014, 56: 862–871.CrossRefGoogle Scholar
  4. [4]
    YAN Liang, DU Feng-shan, DAI Sheng-long, YANG Shou-jie. Effect of age condition on fatigue properties of 2E12 aluminum alloy [J]. Journal of Central South University of Technology, 2010, 17: 697–702.CrossRefGoogle Scholar
  5. [5]
    MORRIS D G, MUNOZ-MORRIS M A. Microstructure of severely deformed Al-3Mg and its evolution during annealing [J]. Acta Materialia, 2002, 50(16): 4047–4060.CrossRefGoogle Scholar
  6. [6]
    SMOLA B, STULÍKOVÁI I, OCENÁŠEK V, PELCOVÁ J, NEUBERT V. Annealing effects in Al–Sc alloys [J]. Materials Science and Engineering A, 2007, 462(1, 2): 370–374.CrossRefGoogle Scholar
  7. [7]
    SHI Yun-jia, PAN Qing-lin, LI Meng-jia, HUANG Xing, LI Bo. Influence of alloyed Sc and Zr, and heat treatment on microstructures and stress corrosion cracking of Al–Zn–Mg–Cu alloys [J]. Materials Science and Engineering A, 2015, 621: 173–181.CrossRefGoogle Scholar
  8. [8]
    WEN Kai, FAN Yun-qiang, WANG Guo-jun, JIN Long-bin, LI Xi-wu, LI Zhi-hui, ZHANG Yong-gan, XIONG Bai-qing. Aging behavior and precipitate characterization of a high Zn-containing Al–Zn–Mg–Cu alloy with various tempers [J]. Materials & Design, 2016, 101: 16–23.CrossRefGoogle Scholar
  9. [9]
    FENG Lei, PAN Qing-lin, WEI Li-li, HUANG Zhi-qi, LIU Zhi-ming. Through-thickness inhomogeneity of localized corrosion in 7050-T7451 Al alloy thick plate [J]. Journal of Central South University, 2015, 22(7): 2423–2434.CrossRefGoogle Scholar
  10. [10]
    ZHANG Zhi-ye, PAN Qing-lin, ZHOU Jian. Hot deformation behavior and microstructure evolution of Al–Zn–Mg–0.25Sc–Zr alloy during compression at elevated temperatures [J]. Transaotions of Nonferrous Metals Society of China, 2012, 22(7): 1556–1562.CrossRefGoogle Scholar
  11. [11]
    PEREZ M, DUMONT M, ACEVEDO-REYES D. Implementation of classical nucleation and growth theories for precipitation [J]. Acta Materialia, 2008, 56(9): 2119–2132.CrossRefGoogle Scholar
  12. [12]
    ROKHLIN L L, DOBATKINA T V, BOCHVAR N R, LYSOVA E V. Investigation of phase equilibria in alloys of the Al–Zn–Mg–Cu–Zr–Sc system [J]. Journal of Alloys and Compounds, 2004, 367(1, 2): 10–16.CrossRefGoogle Scholar
  13. [13]
    SENKOV O N, SHAGIEV M R, SENKOVA S V, MIRACLE D B. Precipitation of Al3(Sc,Zr) particles in an Al–Zn–Mg–Cu–Sc–Zr alloy during conventional solution heat treatment and its effect on tensile properties [J]. Acta Materialia, 2008, 56(15): 3723–3738.CrossRefGoogle Scholar
  14. [14]
    YAN Jie, PAN Qing-lin, ZHANG Xiang-kai, SUN Xue, LI An-de, ZHOU Xun. Characterization of hot deformation behavior of Al–Zn–Mg–Mn–Zr alloy during compression at elevated temperature [J]. Journal of Central South University, 2017, 24(3): 515–520.CrossRefGoogle Scholar
  15. [15]
    ROBSON J D, PRANGNELL P B. Dispersoid precipitation and process modelling in zirconium containing commercial aluminium alloys [J]. Acta Materialia, 2001, 49(4): 599–613.CrossRefGoogle Scholar
  16. [16]
    RIDDLE Y W, SANDERS T H. A study of coarsening, recrystallization, and morphology of microstructure in Al–Sc–(Zr)–(Mg) alloys [J]. Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science, 2004, 35A(1): 341–350.CrossRefGoogle Scholar
  17. [17]
    HUANG Xing, PAN Qing-lin, LI Bo, LIU Zhi-ming, HUANG Zhi-qi, YIN Zhi-min. Effect of minor Sc on microstructure and mechanical properties of Al–Zn–Mg–Zr alloy metal–inert gas welds [J]. Journal of Alloys and Compounds, 2015, 629: 197–207.CrossRefGoogle Scholar
  18. [18]
    ZHAO Jun-wen, XU Chao, CAI Guang-ze, WU Shu-sen, HAN Jing. Microstructure and properties of rheo-diecasting wrought aluminum alloy with Sc additions [J]. Materials Letters, 2016, 173: 22–25.CrossRefGoogle Scholar
  19. [19]
    OROWAN E. Theory of the fatigue of metals [J]. Proceedings of the Royal Society of London Series A-Mathematical and Physical Sciences, 1939, 171(A994): 0079–0106.CrossRefzbMATHGoogle Scholar
  20. [20]
    SARHAN A A D, ZALNEZHAD E, HAMDI M. The influence of higher surface hardness on fretting fatigue life of hard anodized aerospace AL7075-T6 alloy [J]. Materials Science and Engineering A, 2013, 560: 377–387.CrossRefGoogle Scholar
  21. [21]
    LI Meng-jia, PAN Qing-lin, WANG Ying, SHI Yun-jia. Fatigue crack growth behavior of Al–Mg–Sc alloy [J]. Materials Science and Engineering A, 2014, 598: 350–354.CrossRefGoogle Scholar
  22. [22]
    PARIS P C. The growth of cracks due to variations in load [D]. Lehigh University, 1962.Google Scholar
  23. [23]
    GUAN Ming-fei, YU Hao. Fatigue crack growth behaviors in hot-rolled low carbon steels: A comparison between ferrite–pearlite and ferrite–bainite microstructures [J]. Materials Science and Engineering A, 2013, 559: 875–881.CrossRefGoogle Scholar
  24. [24]
    HUTCHINSON C R, de GEUSER F, CHEN Y, DESCHAMPS A. Quantitative measurements of dynamic precipitation during fatigue of an Al–Zn–Mg–(Cu) alloy using small-angle X-ray scattering [J]. Acta Materialia, 2014, 74: 96–109.CrossRefGoogle Scholar
  25. [25]
    HAN W Z, VINOGRADOV A, HUTCHINSON C R. On the reversibility of dislocation slip during cyclic deformation of Al alloys containing shear-resistant particles [J]. Acta Materialia, 2011, 59(9): 3720–3736.CrossRefGoogle Scholar
  26. [26]
    WANG Yin-lin, PAN Qing-lin, WEI Li-li, LI Bo, WANG Ying. Effect of retrogression and reaging treatment on the microstructure and fatigue crack growth behavior of 7050 aluminum alloy thick plate [J]. Materials & Design, 2014, 55: 857–863.CrossRefGoogle Scholar
  27. [27]
    ZHAO Y L, TANG Z Q, ZHANG Z, SU G Y, MA X L. Double-peak age strengthening of cold-worked 2024 aluminum alloy [J]. Acta Materialia, 2013, 61(5): 1624–1638.CrossRefGoogle Scholar
  28. [28]
    WEI Li-li, PAN Qing-lin, HUANG Xing, FENG Lei, WANG Ying. Influence of grain structure and crystallographic orientation on fatigue crack propagation behavior of 7050 alloy thick plate [J]. International Journal of Fatigue, 2014, 66: 55–64.CrossRefGoogle Scholar
  29. [29]
    SHI Yun-jia, PAN Qing-lin, LI Meng-jia, HUANG Xing, LI Bo. Effect of Sc and Zr additions on corrosion behaviour of Al–Zn–Mg–Cu alloys [J]. Journal of Alloys and Compounds, 2014, 612: 42–50.CrossRefGoogle Scholar
  30. [30]
    LI Chen, PAN Qing-lin, SHI Yun-jia, WANG Ying, LI Bo. Influence of aging temperature on corrosion behavior of Al–Zn–Mg–Sc–Zr alloy [J]. Materials & Design, 2014, 55: 551–559.CrossRefGoogle Scholar
  31. [31]
    MARLAUD T, DESCHAMPS A, BLEY F, LEFEBVRE W, BAROUX B. Evolution of precipitate microstructures during the retrogression and re-ageing heat treatment of an Al–Zn–Mg–Cu alloy [J]. Acta Materialia, 2010, 58(14): 4814–4826.CrossRefGoogle Scholar
  32. [32]
    GUO Wei, YANG Meng, ZHENG Yi, ZHANG Xue-shu, LI Hui, WEN Xi-yu, ZHANG Jing-wu. Influence of elastic tensile stress on aging process in an Al–Zn–Mg–Cu alloy [J]. Materials Letters, 2013, 106: 14–17.CrossRefGoogle Scholar
  33. [33]
    LI Gen, ZHAO Nai-qin, LIU Tao, LI Jia-jun, HE Chun-nian, SHI Chun-sheng, LIU En-zuo, SHA Jun-wei. Effect of Sc/Zr ratio on the microstructure and mechanical properties of new type of Al–Zn–Mg–Sc–Zr alloys [J]. Materials Science and Engineering A, 2014, 617: 219–227.CrossRefGoogle Scholar
  34. [34]
    NIKULIN I, KIPELOVA A, MALOPHEYEV S, KAIBYSHEV R. Effect of second phase particles on grain refinement during equal-channel angular pressing of an Al–Mg–Mn alloy [J]. Acta Materialia, 2012, 60(2): 487–497.CrossRefGoogle Scholar
  35. [35]
    CAVALIERE P, CABIBBO M. Effect of Sc and Zr additions on the microstructure and fatigue properties of AA6106 produced by equal-channel-angular-pressing [J]. Materials Characterization, 2008, 59(3): 197–203.CrossRefGoogle Scholar
  36. [36]
    LAIRD C, SMITH G C. Crack propagation in high stress fatigue [J]. Philosophical Magazine, 1962, 7(77): 847–857.CrossRefGoogle Scholar

Copyright information

© Central South University Press and Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  • Jing Chen (陈婧)
    • 1
  • Qing-lin Pan (潘清林)
    • 1
  • Xue-hong Yu (虞学红)
    • 1
  • Meng-jia Li (李梦佳)
    • 1
  • Hao Zou (邹浩)
    • 1
  • Hao Xiang (向浩)
    • 1
  • Zhi-qi Huang (黄志其)
    • 2
  • Quan Hu (胡权)
    • 2
  1. 1.School of Materials Science and EngineeringCentral South UniversityChangshaChina
  2. 2.Guangdong Fenglu Aluminum Co., LtdFoshanChina

Personalised recommendations