The influence of the ageing temperature on different properties of the EN AW-7075 aluminium alloy




Ageing, Electrical conductivity, EN AW-7075, Hardness, Thermal properties


The influence of the ageing temperature on the hardness, electrical conductivity, thermal diffusivity and thermal conductivity of the EN AW-7075 aluminium alloy was studied in this paper. After solution treating the alloy at 480 °C for 1 h and quenching it in ice water, the investigated alloy was characterized using Differential Thermal Analysis (DTA) in order to determine the optimal temperatures for the isochronal ageing treatments. Afterwards, isochronal ageing was conducted at the temperature range of 110 °C-250 °C for 30 min The hardness, electrical conductivity, thermal diffusivity, thermal conductivity and microstructural features were investigated during the ageing treatments. Hardness had a peak value after ageing at 150 °C, while other properties gradually increased with the ageing temperature. Microstructural investigation of the aged alloy by SEM-EDS revealed the existence of precipitated phases that appear homogenously distributed in the microstructure.


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ASTM E384-22 (2022). Standard Test Method for Microindentation Hardness of Materials. ASTM International, West Conshohocken, PA, USA.

Cai, S.W., He, Y., Song, R.G. (2020). Study on the Strengthening Mechanism of Two-Stage Double-Peaks Aging in 7075 Aluminum Alloy. Trans. Indian Iinst. Met. 73 (1), 109-117.

Chen, G., Chen, Q., Wang, B., Du, Z.-M. (2015). Microstructure evolution and tensile mechanical properties of thixoformed high performance Al-Zn-Mg-Cu alloy. Met. Mater. Int. 21 (5), 897-906.

Choi, S.W. Cho, H.S., Kang, C.S., Kumai,S. (2015). Precipitation dependence of thermal properties for Al-Si-Mg-Cu-(Ti) alloy with various heat treatment. J. Alloys Compd. 647, 1091-1097.

Cui, L., Liu, Z., Zhao, Xi., Tang, J., Liu, K., Liu, X., Qian, C. (2014). Precipitation of metastable phases and its effect on electrical resistivity of Al-0.96Mg2Si alloy during aging. Trans. Nonferrous. Met. Soc. China 24 (7), 2266-2274.

Dos Santos, S.L., Toloczko, F.R., Merij, A.C., Saito, N.H., Da Silva, D.M. (2021). Investigation and Nanomechanical Behavior of the Microconstituents of Al-Si-Cu alloy After Solution and Ageing Heat Treatments. Mater. Res. 24 (2), e20200329.

Edwards, G.A., Stiller, K., Dunlop, G.L., Couper, M.J. (1998). The precipitation sequence in Al-Mg-Si alloys. Acta Mater. 46 (11), 3893-3904.

Fallahi, A., Hosseini-Tudeshky, H., Ghalehbandi, S.M. (2013). Effect of heat treatment on mechanical properties of ECAPed 7075 aluminum alloy. Adv. Mat. Res. 829, 62-66.

Fan, Y., Tang, X., Wang, S., Chen, B. (2021). Comparisons of Age Hardening and Precipitation Behavior in 7075 Alloy Under Single and Double-Stage Aging Treatments. Met. Mater. Int. 27, 4204-4215.

Goswami, R., Lynch, S., Holroyd N.J.H., Knight, S.P., Holtz R.L. (2013). Evolution of Grain Boundary Precipitates in Al 7075 Upon Aging and Correlation with Stress Corrosion Cracking Behavior. Metall. Mater. Trans. A. 44, 1268-1278.

Greb, T., Mittler, T., Schmid, S., Volk, W., Chen, H., Khalifa, N.B. (2019). Thermal analysis and production of As-Cast Al 7075/6060 Bilayer billets. Int. J. Metalcast. 13 (4), 817-829.

Hebbar, S., Kertsch, L., Butz, A. (2020). Optimizing Heat Treatment Parameters for the W-Temper Forming of 7xxx Series Aluminum Alloys. Metals 10 (10), 1361.

Kacar, R., Guleryuz, K. (2015). Effect of Quenching Rate and Pre-strain on the Strain Ageing Behaviors of 7075 Aluminum Alloys. Mater. Res. 18 (2), 328-333.

Khangholi, S.N., Javidani, M., Maltais, A., Chen, X. (2021). Effects of natural aging and pre-aging on the strength and electrical conductivity in Al-Mg-Si AA6201 conductor alloys. Mater. Sci. Eng. A. 820, 141538.

Kilic, S., Kacar, I., Sahin, M., Ozturk, F., Erdem, O. (2019). Effects of Aging Temperature, Time, and Pre-Strain on Mechanical Properties of AA7075. Mater. Res. 22 (5), e20190006.

Ku, M.H., Hung, F.Y., Lui, T.S., Lai, J.J. (2018). Enhanced Formability and Accelerated Precipitation Behavior of 7075 Al Alloy Extruded Rod by High Temperature Aging. Metals. 8 (8), 648.

Liu, Y., Zhu, B., Wang, Y., Li, S., Zhang, Y. (2020). Fast solution heat treatment of high strength aluminum alloy sheets in radiant heating furnace during hot stamping. Int. J. Lightweight Mater. 3 (1), 20-25.

Lumley, R.G., Deeva, N., Larsen, R., Gemberovic, J., Freeman J. (2013). The Role of Alloy Composition and T7 Heat Treatment in Enhancing Thermal Conductivity of Aluminum High Pressure Diecastings. Metall. Mater. Trans. A. 44 (2), 1074-1086.

MacKenzie, D.S. (2000). Quench rate and ageing effects in aluminum-zinc-magnesium-copper aluminum alloys. PhD Thesis, Faculty of the Graduate School of the University of Missouri-Rolla, Missouri, USA.

Mukhopadhyay, A.K., Yang, Q.B., Singh, S.R. (1994). The influence of zirconium on the early stages of aging of a ternary Al-Zn-Mg alloy. Acta Metall. Mater. 42 (9), 3083-3091.

Nicolas, M. (2002). Precipitation evolution in an Al-Zn-Mg alloy during non-isothermal heat treatments and in the heat-affected zone of welded joints. PhD Thesis, The Grenoble Institute of Technology, Grenoble, France.

Ozer, G., Karaaslan, A. (2017). Properties of AA7075 aluminum alloy in aging and retrogression and reaging process. Trans. Nonferrous. Met. Soc. China 27 (11), 2357-2362.

Padap, A.K., Yadav, A.P., Kumar, P., Kumar, N. (2020). Effect of aging heat treatment and uniaxial compression on thermal behavior of 7075 aluminum alloy. Mater. Today: Proc. 33 (8), 5442-5447.

Pan, H., Yue, H., Zhang, X. (2021). Interactions between Dislocations and Boundaries during Deformation. Materials 14 (4), 1012. PMid:33669924 PMCid:PMC7924853

Panigrahi, S.K., Jayaganthan, R. (2011). Effect of Annealing on Thermal Stability, Precipitate Evolution, and Mechanical Properties of Cryorolled Al 7075 Alloy. Metall. Mater. Trans. A. 42 (10), 3208-3217.

Pankade, S.B., Khedekar, D.S., Gogte, C.L. (2018). The influence of heat treatments on electrical conductivity and corrosion performance of AA 7075-T6 aluminium alloy. Procedia Manuf. 20, 53-58.

Sha, G., Cerezo, A. (2004). Early-stage precipitation in Al-Zn-Mg-Cu alloy (7050). Acta Mater. 52 (15), 4503-4516.

Salazar-Guapuriche, M.A., Zhao, Y.Y., Pitman, A., Greene, A. (2006). Correlation of Strength with Hardness and Electrical Conductivity for Aluminium Alloy 7010. Mater. Sci. Forum. 519-521, 853-858.

Sambathkumara, M., Sasikumara K.S.K., Gukendrana R., Dineshkumara K., Ponappab K., Harichandran S. (2021). Investigation of mechanical and corrosion properties of Al 7075/Redmud metal matrix composite. Rev. Metal. 57 (1), e185.

Siddiqui, R.A., Abdullah, H.A., Al-Belushi, K.R. (2000). Influence of aging parameters on the mechanical properties of 6063 aluminium alloy. J. Mater. Process. Technol. 102 (1-3), 234-240.

Simsek, I. (2019). Investigation of the effect of second phase precipitates on the corrosion and electrical conductivity of 7075 aluminum alloys. Anti-Corros. Method. M. 66 (5), 683-688.

Woznicki, A., Leszczynska-Madej, B., Wloch, G., Grzyb, J., Madura, J., Lesniak, D. (2021). Homogenization of 7075 and 7049 Aluminium Alloys Intended for Extrusion Welding. Metals 11 (2), 338.

Yang, X., Liu, J., Chen, J., Wan, C., Feng, L., Liu, P., Wu, C. (2014). Relationship Between the Strengthening Effect and the Morphology of Precipitates in Al-7.4Zn-1.7Mg-2.0Cu Alloy. Acta Metall. Sin. 27, 1070-1077



How to Cite

Stamenković, U. ., Ivanov, S., Marković, I., Gorgievski, M., Božinović, K., & Kovačević, A. . (2023). The influence of the ageing temperature on different properties of the EN AW-7075 aluminium alloy. Revista De Metalurgia, 59(1), e238.




Funding data

Univerzitet u Beogradu
Grant numbers 451-03-47/2023-01/200131

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