Effect of RRA Treatment on the Properties and Microstructural Evolution of Al–Zn–Mg–Cu–Er–Zr Alloy

  • Xiaofei Wang
  • Zuoren Nie
  • Hui Huang
  • Shengping Wen
  • Kunyuan Gao
  • Xiaolan Wu
Conference paper

Abstract

Effect of RRA treatment on the mechanical properties and microstructure of Al–Zn–Mg–Cu–Er–Zr aluminium alloy was researched by hardness measurement, conductivity measurement, exfoliation corrosion measurement, transmission electron microscopy (TEM). Discussed the relationship between the regression treatment and composite properties of the alloy. The study found that the hardness of RRA treated alloys first rise and then decline with the increasing of regression time, but the corrosion performance is increasing all the time. After pre-aging treatment 120 °C/24 h, regression treatment 180 °C/60 min, re-aging treatment 120 °C/24 h, the combination property of the alloy is optimal, the hardness, conductivity and the exfoliation corrosion grade are respectively: 207.6 HV, 33.53%IACS, PC. At this moment, it is found from the TEM observations that the matrix precipitates are small and dispersed, resemble to T6 temper. The grain boundary precipitation out phases are discontinuous distribution and the relatively wider PFZ, similar to the T73 temper.

Keywords

Al–Zn–Mg–Cu–Er–Zr alloy RRA treatment Mechanical property Corrosion properties TEM microstructures 

Notes

Acknowledgements

The authors would acknowledge support from National Natural Science Foundation of China (51671005), Beijing Natural Science Foundation (2162006), the National Key Research and Development Program of China (2016YFB0300804 and 2016YFB0300801), National Natural Science Fund for Innovative Research Groups (51621003) and Program on Jiangsu Key Laboratory for Clad Materials (BM2014006).

References

  1. 1.
    Heinz A, Haszler A, Keidel C, Moldenhauer S, Benedictus R, Miller WS. Recent development in aluminium alloys for aerospace applications. Mater Sci Eng A. 280 (2000) 102.Google Scholar
  2. 2.
    Williams JC, Starke EA. Progress in structural materials for aerospace systems. Acta Mater. 51 (2003) 5775.Google Scholar
  3. 3.
    Dursun T, Soutis C. Recent developments in advanced aircraft aluminium alloys. Mater Des.56 (2014) 862.Google Scholar
  4. 4.
    R. Ferragut, A. Somoza, A. Tolley, Microstructural evolution of 7012 alloy during the early stages of artificial ageing, Acta Materialia. 47 (1999) 4355-4364.Google Scholar
  5. 5.
    B.L. Qu. J.G. Yang, Effects of step quench and aging on mechanical properties and resistance to stress corrosion cracking of 7050 aluminium alloy, Material Transactions. 41 (2000) 783–789.Google Scholar
  6. 6.
    Song FX, Zhang XM, Liu SD, Tan Q, Li DF. Exfoliation corrosion behavior of 7050-T6 aluminum alloy treated with various quench transfer time. Trans. Nonferr. Met Soc China. 24 (2014) 2258.Google Scholar
  7. 7.
    Song FX, Zhang XM, Liu SD, Tan Q, Li DF. The effect of quench transfer time on microstructure and localized corrosion behavior of 7050-T6 Al alloy. Mater Corros. 65 (2014) 1007.Google Scholar
  8. 8.
    Wang D, Ni DR, Ma ZY. Effect of pre-strain and two-step aging on microstructure and stress corrosion cracking of 7050 alloy. Mater Sci Eng A. 494 (2008) 360.Google Scholar
  9. 9.
    Deng Y, Yin ZM, Zhao K, Duan JQ, Hu J, He ZB. Effects of Sc and Zr micro alloying additions and aging time at 120 °Con the corrosion behavior of an Al-Zn-Mg alloy. Corros Sci. 65 (2012) 288.Google Scholar
  10. 10.
    Yang W, Ji S, Zhang Q, Wang M. Investigation of mechanical and corrosion properties of an Al-Zn-Mg-Cu alloy under various ageing conditions and interface analysis of η, precipitate. Mater. Des. 85 (2015) 752.Google Scholar
  11. 11.
    Cina BM. Reducing the susceptibility of alloys, particularly aluminium alloys, to stress corrosion cracking. US Patent. 3856584. (1974).Google Scholar
  12. 12.
    Talianker M, Cina B. Retrogression and re-aging and the role of dislocations in the stress corrosion of 7000-type aluminum alloys. Metall Mater Trans A. 20 (1989) 2087.Google Scholar
  13. 13.
    Park JK, Ardell AJ. Effect of retrogression and re-aging treatments on the microstructure of Ai-7075-T651. Metall Trans A. 15 (1984) 1531.Google Scholar
  14. 14.
    Oliveira AF, Barros MCD, Cardoso KR, Travessa DN. The effect of RRA on the strength and SCC resistance on AA7050 and AA7150 aluminium alloys. Mater Sci Eng A. 379 (2004) 321.Google Scholar
  15. 15.
    Ranganatha R, Kumar V A, Nandi V S, et al. Multi-stage heat treatment of aluminum alloy AA7049 [J]. Transactions of Nonferrous Metals Society of China. 23 (2013) 1570–1575.Google Scholar
  16. 16.
    Fang S F, Wang M P, Song M. An approach for the aging process optimization of Al–Zn–Mg–Cu series alloys [J]. Materials & Design. 30 (2009) 2460–2467.Google Scholar

Copyright information

© Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  • Xiaofei Wang
    • 1
  • Zuoren Nie
    • 1
  • Hui Huang
    • 1
  • Shengping Wen
    • 1
  • Kunyuan Gao
    • 1
  • Xiaolan Wu
    • 1
  1. 1.School of Materials Science and EngineeringBeijing University of TechnologyBeijingPeople’s Republic of China

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