Abstract
To obtain better comprehensive properties of cast Al-Cu-Mg alloys, the secondary aging (T6I6) process (including initial aging, interrupted aging and re-aging stages) was optimized by an orthogonal method. The microstructures of the optimized Al-Cu-Mg alloy were observed by means of scanning electron microscopy and transmission electron microscopy, and the properties were investigated by hardness measurements, tensile tests, exfoliation corrosion tests, and intergranular corrosion tests. Results show that the S phase and θ′ phase simultaneously exist in the T6I6 treated alloy. Appropriately increasing the temperature of the interrupted aging in the T6I6 process can improve the mechanical properties and corrosion resistance of Al-Cu-Mg alloy. The optimal comprehensive properties (tensile strength of 443.6 MPa, hardness of 161.6 HV) of the alloy are obtained by initial aging at 180 °C for 2 h, interrupted aging at 90 °C for 30 min, and re-aging at 170 °C for 4 h.
Article PDF
Similar content being viewed by others
References
Du A H, Wang W G, Gu X F, et al. The dependence of precipitate morphology on the grain boundary types in an aged Al-Cu binary alloy. Journal of Materials Science, 2021, 56(1): 781–791.
Liu F, Liu Z Y, Liu M, et al. Analysis of empirical relation between microstructure, texture evolution and fatigue properties of an Al-Cu-Li alloy during different pre-deformation processes. Materials Science and Engineering A, 2019, 726: 309–319.
Shi W N, Zhou H F, Zhang X F. High-strength and anti-corrosion of Al-Cu-Mg alloy by controlled ageing process. Philosophical Magazine Letters, 2019, 99(7): 235–242.
Qi Z W, Cong B Q, Qi B J, et al. Microstructure and mechanical properties of double-wire plus arc additively manufactured Al-Cu-Mg alloys. Journal of Materials Processing Technology, 2018, 255: 347–353.
Zainul H, Nur I T, Tuan Z. Characterization of 2024-T3: An aerospace aluminum alloy. Materials Chemistry and Physics, 2009, 113(2–3): 151–157.
Barros A, Cruz C, Silva A P, et al. Length scale of solidification microstructure tailoring corrosion resistance and microhardness in T6 heat treatment of an Al-Cu-Mg alloy. Corrosion Engineering Science and Technology, 2020, 55(6): 471–479.
Niu P L, Lia W Y, Lia N, et al. Exfoliation corrosion of friction stir welded dissimilar 2024-to-7075 aluminum alloys. Materials Characterization, 2019, 147: 93–100.
Marceau R K W, Sha G, Lumley R N, et al. Evolution of solute clustering in Al-Cu-Mg alloys during secondary ageing. Acta Materialia, 2010, 58(5): 1795–1805.
Gao N, Starink M J, Kamp N, et al. Application of uniform design in optimisation of three stage ageing of Al-Cu-Mg alloys. Journal of Materials Science, 2007, 42(12): 4398–4405.
Ye L Y, Gu G, Zhang X M, et al. Dynamic properties evaluation of 2519A aluminum alloy processed by interrupted aging. Materials Science and Engineering A, 2014, 590(1): 97–100.
Lumley R N, Polmear I J, Morton A J. Heat treatment of age hardenable aluminium alloys utilizing secondary precipitation. US Patent No. 7037391 B2, 2006-05-02.
Xu X H, Deng Y L, Chi S Q, et al. Effect of interrupted ageing treatment on the mechanical properties and intergranular corrosion behavior of Al-Mg-Si alloys. Journal of Materials Research and Technology, 2020, 9(1): 230–241.
Buha J, Lumley R N, Crosky A G, et al. Secondary precipitation in an Al-Mg-Si-Cu alloy. Acta Materialia, 2007, 55(9): 3015–3024.
Chen Y, Weyland M, Hutchinson C R. The effect of interrupted aging on the yield strength and uniform elongation of precipitation-hardened Al alloys. Acta Materialia, 2013, 61: 5877–5894.
Lumley R N, Polmear I J, Morton A J. Development of mechanical properties during secondary aging in aluminium alloys. Materials Science and Technology, 2005, 21(9): 1025–1032.
Lumley R N, Polmear I J, Morton A J. Development of properties during secondary ageing of aluminium alloys. Materials Science Forum, 2003, 426–432(4): 303–308.
Yin M J, Chen J H, Liu C H. Effect of interrupted aging treatment on mechanical properties and microstructure of AA2024 aluminum alloy. Transactions of Nonferrous Metals Society of China, 2015, 25(12): 3271–3281. (In Chinese)
Li H, Pan D Z, Wang Z X, et al. Influence of T6I6 temper on tensile and intergranular corrosion properties of 6061 aluminum alloy. Acta Metallurgica Sinica, 2010, 46(4): 494–499. (In Chinese)
Boag A, Taylor R J, Muster T H, et al. Stable pit formation on AA2024-T3 in a NaCl environment. Corrosion Science, 2010, 52(1): 90–103.
Kurtulmus M. Experimental investigation and optimization of welding parameters on weld strength in friction stir spot welding of aluminum using Taguchi experimental design. Emerging Materials Research, 2020, 9(6): 662–667.
Vidal C, Infante V. Optimization of FS welding parameters for improving mechanical behavior of AA2024-T351 joints based on Taguchi method. Journal of Materials Engineering and Performance, 2013, 22(8): 2261–2270.
Xin F H, Liu W H, Song L, et al. Modification of inorganic binder used for sand core-making in foundry practice. China Foundry, 2020, 17(5): 341–346.
Li H Z, Liu R M, Liang X P, et al. Effect of pre-deformation on microstructures and mechanical properties of high purity Al-Cu-Mg alloy. Transactions of Nonferrous Metals Society of China, 2016, 26(6): 1482–1490.
Oltra R, Vuillemin B, Rechou F, et al. Effect of aeration on the microelectrochemical characterization of Al2Cu intermetallic phases. Electrochemical and Solid-State Letters, 2009, 12(12): C29–C31.
Wang S C, Starink M J. Precipitates and intermetallic phases in precipitation hardening Al-Cu-Mg-(Li) based alloys. Acta Materialia, 2005, 50(4): 193–215.
Wang S C, Starink M J. Two types of S phase precipitates in Al-Cu-Mg alloys. Acta Materialia, 2007, 55(3): 933–941.
Kim I S, Song M Y, Kim J H, et al. Effect of added Mg on the clustering and two-step aging behavior of Al-Cu alloys. Materials Science and Engineering A, 2020, 798: 140123.
Warner J S, Gangloff R P. Alloy induced inhibition of fatigue crack growth in age-hardenable Al-Cu alloys. International Journal of Fatigue, 2012, 42: 35–44.
Acknowledgements
This work was financially supported by the Program for National Key Research and Development Plan (No. 2017YFB1104000), the National Natural Science Foundation of China (No. 51574167), the Liaoning Natural Science Foundation (No. 2021-MS-235), and the Science and Technology Program of Liaoning Provincial Department of Education (No. LJGD2020010).
Author information
Authors and Affiliations
Corresponding author
Additional information
Conflict of interest
The authors declare that they have no conflict of interest.
Rui-ming Su Male, Ph. D., Associate Professor. His research interests mainly focus on the preparation of aluminum alloys.
Rights and permissions
About this article
Cite this article
Su, Rm., Jia, Yx., Xiao, J. et al. Effect of secondary aging on microstructure and properties of cast Al-Cu-Mg alloy. China Foundry 20, 71–77 (2023). https://doi.org/10.1007/s41230-023-1049-2
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s41230-023-1049-2