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Retrogression on corrosion behavior of spray formed Al-7075

Published online by Cambridge University Press:  27 June 2017

Ruiming Su ,
Jianhao Su ,
Yingdong Qu ,
Junhua You  and
Rongde Li
Ruiming Su*
Affiliation:
School of Materials Science and Engineering, Shenyang University of Technology, Shenyang 110870, China
Jianhao Su*
Affiliation:
School of Materials Science and Engineering, Shenyang University of Technology, Shenyang 110870, China
Yingdong Qu
Affiliation:
School of Materials Science and Engineering, Shenyang University of Technology, Shenyang 110870, China
Junhua You
Affiliation:
School of Materials Science and Engineering, Shenyang University of Technology, Shenyang 110870, China
Rongde Li
Affiliation:
School of Materials Science and Engineering, Shenyang University of Technology, Shenyang 110870, China
*
a) Address all correspondence to this author. e-mail: suruiming1984@gmail.com
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Abstract

The effects of retrogression and re-aging (RRA) treatment on intergranular corrosion (IGC), exfoliation corrosion (EXCO), stress corrosion cracking (SCC) behavior and microstructure of spray formed Al-7075 were investigated by a scanning electron microscope, a transmission electron microscope, slow strain rate test, and EXCO and IGC test. The results show that the precipitates are redissolved in the matrix of the alloy after retrogression at 200 °C for a suitable time (8 min), and the grain boundary precipitates are discrete and the obvious precipitate free zones are left at the grain boundaries. After RRA with suitable retrogressed time, thin homogeneous dispersive precipitates are separated out again in the matrix. After retrogression at 200 °C for 8 min and re-aging, the ultimate tensile strength, elongation, IGC depth, EXCO rating, and SCC index of spray formed Al-7075 are 791 MPa, 8.5%, 29.8 μm, EA, and 0.155, respectively.

Keywords

Al–alloyspray depositionstress corrosion crackingretrogressionslow strain rate test
Type
Articles
Information
Journal of Materials Research , Volume 32 , Issue 13 , 14 July 2017 , pp. 2621 - 2627
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Copyright
Copyright © Materials Research Society 2017 

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Footnotes

Contributing Editor: Jürgen Eckert

References

REFERENCES

Hu, T., Ma, K., Topping, T.D., Schoenung, J.M., and Lavernia, E.J.: Precipitation phenomena in an ultrafine-grained Al alloy. Acta Mater. 61, 2163–2178 (2013).Google Scholar
Ma, K., Wen, H., Hu, T., Topping, T.D., Isheim, D., Seidman, D.N., Lavernia, E.J., and Schoenung, J.M.: Mechanical behavior and strengthening mechanisms in ultrafine grain precipitation-strengthened aluminum alloy. Acta Mater. 62, 141–155 (2014).CrossRefGoogle Scholar
George, S.L. and Knutsen, R.D.: Composition segregation in semi-solid metal cast AA7075 aluminium alloy. J. Mater. Sci. 47, 4716–4725 (2012).CrossRefGoogle Scholar
Marlaud, T., Deschamps, A., Bley, F., Lefebvre, W., and Baroux, B.: Influence of alloy composition and heat treatment on precipitate composition in Al–Zn–Mg–Cu alloys. Acta Mater. 58, 248–260 (2010).CrossRefGoogle Scholar
Jeyakumar, M., Kumar, S., and Gupta, G.S.: Microstructure and properties of the spray-formed and extruded 7075 Al alloy. Mater. Manuf. Processes 25, 777–785 (2010).CrossRefGoogle Scholar
Jeyakumar, M., Kumar, S., and Gupta, G.S.: The influence of processing parameters on characteristics of an aluminum alloy spray deposition. Mater. Manuf. Processes 24, 693–699 (2009).Google Scholar
Su, R.M., Qu, Y.D., You, J.H., and Li, R.D.: Study on a new retrogression and re-aging treatment of spray formed Al–Zn–Mg–Cu alloy. J. Mater. Res. 31, 573–579 (2016).Google Scholar
Shi, J.L., Yan, H.G., Su, B., Chen, J.H., Zhu, S.Q., and Chen, G.: Preparation of a functionally gradient aluminum alloy metal matrix composite using the technique of spray deposition. Mater. Manuf. Processes 26, 1236–1241 (2011).Google Scholar
Ricker, R.E., Lee, E.U., Taylor, R., Lei, C., Pregger, B., and Lipnickas, E.: Chloride ion activity and susceptibility of Al alloys 7075-T6 and 5083-H131 to stress corrosion cracking. Metall. Mater. Trans. A 44, 1353–1364 (2013).Google Scholar
Rajakumar, S. and Balasubramanian, V.: Predicting grain size, and tensile strength of friction stir welded joints of AA7075-T6 aluminium alloy. Mater. Manuf. Processes 27, 78–83 (2012).Google Scholar
Silva, G., Rivolta, B., Gerosa, R., and Derudi, U.: Study of the SCC behavior of 7075 aluminum alloy after one-step aging at 163 °C. J. Mater. Eng. Perform. 22, 210–214 (2013).Google Scholar
Arnold, E.M., Schubbe, J.J., Moran, P.J., and Bayles, R.A.: Comparison of SCC thresholds and environmentally assisted cracking in 7050-T7451 aluminum plate. J. Mater. Eng. Perform. 21, 2480–2486 (2012).CrossRefGoogle Scholar
Fooladfar, H., Hasnemi, B., and Younesi, M.: The effect of the surface treating and high-temperature aging on the strength and SCC susceptibility of 7075 aluminum alloy. J. Mater. Eng. Perform. 19, 852–859 (2010).Google Scholar
Starink, M.J. and Wang, S.C.: A model for the yield strength of overaged Al–Zn–Mg–Cu alloys. Acta Mater. 51, 5131–5150 (2003).Google Scholar
Wang, D., Ni, D.R., and Ma, Z.Y.: Effect of pre-strain and two-step aging on microstructure and stress corrosion cracking of 7050 alloy. Mater. Sci. Eng., A 494, 360–366 (2008).CrossRefGoogle Scholar
Cina, B.M.: Reducing the susceptibility of alloys, particularly aluminium alloys, to stress corrosion cracking. U.S. Patent No. 3.856.584, December 24, 1974.Google Scholar
Peng, G., Chen, K., Chen, S., and Fang, H.: Influence of repetitious-RRA treatment on the strength and SCC resistance of Al–Zn–Mg–Cu alloy. Mater. Sci. Eng., A 528, 4014–4018 (2011).Google Scholar
Reda, Y., Abdel-Karim, R., and Elmahallawi, I.: Improvements in mechanical and stress corrosion cracking properties in Al-alloy 7075 via retrogression and reaging. Mater. Sci. Eng., A 485, 468–475 (2008).CrossRefGoogle Scholar
Su, R.M., Qu, Y.D., and Li, R.D.: Effect of aging treatments on the mechanical and corrosive behaviors of spray-formed 7075 alloy. J. Mater. Eng. Perform. 23, 3842–3848 (2014).Google Scholar
Su, R.M., Qu, Y.D., You, J.H., and Li, R.D.: Study on microstructure, mechanical properties and corrosion behavior of spray formed 7075 alloy. Mater. Today Commun. 4, 109–115 (2015).Google Scholar
Ohnishi, T., Ibaraki, Y., and Ito, T.: Improvement of fracture toughness in 7475 aluminum alloy by the RRA (retrogression and re-aging) process. Mater. Trans. JIM 30, 601–607 (1989).CrossRefGoogle Scholar
Oliveira, A.F. Jr., De Barros, M.C., Cardoso, K.R., and Travessa, D.N.: The effect of RRA on the strength and SCC resistance on AA7050 and AA7150 aluminium alloys. Mater. Sci. Eng., A 379, 321–326 (2004).CrossRefGoogle Scholar
Marlaud, T., Deschamps, A., Bley, F., Lefebvre, W., and Baroux, B.: Evolution of precipitate microstructures during the retrogression and re-ageing heat treatment of an Al–Zn–Mg–Cu alloy. Acta Mater. 58, 4814–4826 (2010).Google Scholar
Wu, X.J., Raizenne, M.D., Holt, R.T., Poon, C., and Walllace, W.: Thirty years of retrogression and re-aging (RRA). Can. Aeronaut. Space J. 47, 131–138 (2001).Google Scholar
Bai, P., Hou, X., Zhang, X., Zhao, C., and Xing, Y.: Microstructure and mechanical properties of a large billet of spray formed Al–Zn–Mg–Cu alloy with high Zn content. Mater. Sci. Eng., A 508, 23–27 (2009).Google Scholar
Salamci, E.: Ageing behaviour of spray cast Al–Zn–Mg–Cu alloys. Turk. J. Eng. Environ. Sci. 25, 681–686 (2001).Google Scholar
Salamci, E.: Mechanical properties of spray cast 7XXX series aluminum alloys. Turk. J. Eng. Environ. Sci. 26, 345–352 (2002).Google Scholar
Sha, G. and Cerezo, A.: Early-stage precipitation in Al–Zn–Mg–Cu alloy (7050). Acta Mater. 52, 4503–4516 (2004).Google Scholar
Berg, L.K., Gjønnes, J., Hansen, V., Li, X.Z., Knutson-Wedel, M., Waterloo, G., Schryvers, D., and Wallenberg, L.R.: GP-zones in Al–Zn–Mg alloys and their role in artificial aging. Acta Mater. 49, 3443–3451 (2001).Google Scholar
Jiang, H. and Faulkner, R.G.: Modelling of grain boundary segregation, precipitation and precipitate-free zones of high strength aluminium alloys—I. The model. Acta Mater. 44, 1857–1864 (1996).Google Scholar
Jiang, H. and Faulkner, R.G.: Modelling of grain boundary segregation, precipitation and precipitate-free zones of high strength aluminium alloys—II. Application of the models. Acta Mater. 44, 1865–1871 (1996).CrossRefGoogle Scholar