Hostname: page-component-586b7cd67f-t8hqh Total loading time: 0 Render date: 2024-11-26T20:53:55.010Z Has data issue: false hasContentIssue false

Study on a new retrogression and re-aging treatment of spray formed Al–Zn–Mg–Cu alloy

Published online by Cambridge University Press:  26 February 2016

Rui-ming Su*
Affiliation:
School of Materials Science and Engineering, Shenyang University of Technology, Shenyang 110870, Liaoning, China
Ying-dong Qu
Affiliation:
School of Materials Science and Engineering, Shenyang University of Technology, Shenyang 110870, Liaoning, China
Jun-hua You
Affiliation:
School of Materials Science and Engineering, Shenyang University of Technology, Shenyang 110870, Liaoning, China
Rong-de Li
Affiliation:
School of Materials Science and Engineering, Shenyang University of Technology, Shenyang 110870, Liaoning, China
*
a) Address all correspondence to this author. e-mail: [email protected]
Get access

Abstract

Conventional retrogression and re-aging (RRA) treatment could not be put to good use for combination property of Al–Zn–Mg–Cu alloys. The new RRA treatment fitted for spray formed Al–Zn–Mg–Cu alloy was investigated by transmission electron microscope, tensile, and conductivity tests. The results show that the pre-aging treatment with under aging of 120 °C for 16 h is beneficial for the redissolution of matrix precipitates during retrogression treatment. With the retrogression of 200 °C for 8 min, grain boundary precipitates are discrete and the corrosion resistance of the alloy is drastically increased. After re-aging (120 °C for 24 h) the strength of the alloy is increased again. According to the above-mentioned new RRA treatment, the ultimate tensile strength, yield strength, elongation, and conductivity of the alloy are 791 MPa, 736 MPa, 8.5%, and 39.5% IACS respectively, which is higher than that after conventional RRA treatment.

Type
Articles
Copyright
Copyright © Materials Research Society 2016 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

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, 141155 (2014).Google Scholar
Rajamuthamilselvan, M. and Ramanathan, S.: Hot-working behavior of 7075 Al/15% SiCp composites. Mater. Manuf. Processes 27, 260266 (2012).Google Scholar
Maranhão, C., Davim, J.P., and Jackson, M.J.: Physical thermomechanical behavior in machining an aluminium alloy (7075-O) using polycrystalline diamond tool. Mater. Manuf. Processes 26, 10341040 (2011).Google Scholar
Rajakumar, S., Balasubramanian, V.: Predicting grain size, and tensile strength Of friction stir welded joints of AA7075-T6 aluminium alloy. Mater. Manuf. Processes 27, 7883 (2012).Google Scholar
George, S.L. and Knutsen, R.D.: Composition segregation in semi-solid metal cast AA7075 aluminium alloy. J. Mater. Sci. 47, 47164725 (2012).Google Scholar
Marlaud, T., Deschamps, A., Bley, F., Lefebvrec, W., and Baroux, B.: Influence of alloy composition and heat treatment on precipitate composition in Al–Zn–Mg–Cu alloys. Acta Mater. 58, 248260 (2010).Google Scholar
Marlaud, T., Deschamps, A., Bley, F., Lefebvrec, 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, 48144826 (2010).Google Scholar
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, 21632178 (2013).Google Scholar
Su, R.M., Qu, Y.D., You, J.H., and Li, R.D.: Effect of pre-aging on stress corrosion cracking of spray-formed 7075 alloy in retrogression and re-aging. J. Mater. Eng. Perform. 24, 43284332 (2015).Google 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, 777785 (2010).Google Scholar
Jeyakumar, M., Kumar, S., and Gupta, G.S.: The influence of processing parameters on characteristics of an aluminum alloy spray deposition. Mater. Manuf. Process. 24(6), 693699 (2009).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. Process 26, 12361241 (2011).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, 210214 (2013).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, 13531364 (2013).Google Scholar
Zhang, G., Chen, Z., Zhu, X., Chen, G., Zhai, J., and Guo, A.: The heat treatment behavior of super-high strength aluminum alloys by spray forming. J. Mater. Sci. Chem. Eng. 1, 5760 (2013).Google 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, 852859 (2010).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, 24802486 (2012).CrossRefGoogle Scholar
Cina, B.M.: Reducing the susceptibility of alloys, particularly aluminium alloys, to stress corrosion cracking. US Patent No. 3856584, 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, 40144018 (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, 468475 (2008).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, 109115 (2015).Google 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, 38423848 (2014).Google Scholar
Ohnishi, T. and Shiota, H.: Heat treatment to reduce the susceptibility of Al-Zn-Mg-Cu alloy to stress corrosion cracking. J. Jpn. Inst. Light Met. 36, 647656 (1986). (In Japanese).Google Scholar
Lin, J. and Kersker, M.M.: Heat treatment of precipitation hardening alloy. US Patent No. 5108520. April 28, 1992.Google Scholar
Islam, M.U. and Wallace, W.: Retrogression and reaging response of 7475 aluminium alloy. Mater. Sci. Technol. 10, 386392 (1983).Google Scholar
Sha, G. and Cerezo, A.: Early-stage precipitation in Al–Zn–Mg–Cu alloy (7050). Acta Mater. 52, 45034516 (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, 34433451 (2001).CrossRefGoogle Scholar