Effects of forced cooling and low temperature aging on microstructure and mechanical properties of FSW joint of 2198-T3/7A04-T6 dissimilar aluminum alloy

doi:10.13251/j.issn.0254-6051.2023.09.002

Abstract

Abstract: 2198-T3/7A04-T6 dissimilar aluminum alloy was friction stir welded under air cooling and forced cooling respectively, and the joint was aged at low temperature after welding. The effects of forced cooling and low temperature aging on the microstructure characteristics and mechanical properties of the welded joint were studied. It's found that a low hardness zone appears in the heat affected zone of the 2198-T3 aluminum alloy side under both conditions, but the hardness value of the low hardness zone of the joint under forced cooling+low temperature aging conditions is significantly higher, reaching 94.5 HV0.1. The average yield strength, tensile strength and elongation of the joint are 312 MPa, 443 MPa, and 8.9%, respectively. The yield strength and tensile strength reach 97.5% and 96.9% of the base material strength, respectively. However, under air cooling and low temperature aging conditions, they are only 89.0% and 91.6% of the base material strength. The main reason for the better mechanical properties of joint under forced cooling and low-temperature aging conditions is that applying forced cooling during the welding can effectively suppress the dissolution and coarsening of θ′ and T1 phases in the low hardness zone of the joint, enabling it to achieve better aging strengthening effect in the subsequent low-temperature aging treatment.

Key words: low temperature aging, underwater friction stir welding, precipitated phase, mechanical properties

CLC Number:

TG156.6

Sun Bo, Nie Jiamin, Li Xiaodan, He Changshu. Effects of forced cooling and low temperature aging on microstructure and mechanical properties of FSW joint of 2198-T3/7A04-T6 dissimilar aluminum alloy[J]. Heat Treatment of Metals, 2023, 48(9): 8-13.

References

[1]GüvenI·, Gürel C. Effects of initial temper condition and postweld heat treatment on the properties of dissimilar friction-stir-welded joints between AA7075 and AA6061 aluminum alloys[J]. Metallurgical and Materials Transactions A, 2014, 45: 3074-3087.
[2]张德芬, 谭盖, 陈孝文, 等. 2A12/7075异种铝合金搅拌摩擦焊接头的组织及性能[J]. 金属热处理, 2017, 42(2): 49-53.
Zhang Defen, Tan Gai, Chen Xiaowen, et al. Microstructure and properties of friction stir welding joint of dissimilar 2A12 and 7075 aluminum alloy[J]. Heat Treatment of Metals, 2017, 42(2): 49-53.
[3]Balaji S, Sujay A, Balachandar K. Conventional and underwater friction stir welded AA2024-T351 aluminium alloy-A comparative analysis[J]. World Journal of Engineering, 2020, 17(6): 795-801.
[4]Rouzbehani R, Kokabi A H, Sabet H, et al. Metallurgical and mechanical properties of underwater friction stir welds of Al7075 aluminum alloy[J]. Journal of Materials Processing Technology, 2018, 262: 239-256.
[5]廖泽鑫, 李承波, 刘胜胆, 等. 焊后时效对7046铝合金搅拌摩擦焊接头力学性能的影响[J]. 材料研究学报, 2021, 35(7): 543-552.
Liao Zexin, Li Chengbo, Liu Shengdan, et al. Effect of post aging on mechanical properties of friction stir welded 7046 aluminum alloy[J]. Chinese Journal of Materials Research, 2021, 35(7): 543-552.
[6]Babu K T, Muthukumaran S, Narayanan C S, et al. Analysis and characterization of forming behavior on dissimilar joints of AA5052-O to AA6061-T6 using underwater friction stir welding[J]. Surface Review and Letters, 2020, 27: 1950121.
[7]Safarbali B, Shamanian M, Eslami A. Effect of post-weld heat treatment on joint properties of dissimilar friction stir welded 2024-T4 and 7075-T6 aluminum alloys[J]. Transactions of Nonferrous Metals Society of China, 2018, 28(7): 1287-1297.
[8]Zhang J, Feng X S, Gao J S, et al. Effects of welding parameters and post-heat treatment on mechanical properties of friction stir welded AA2195-T8 Al-Li alloy[J]. Journal of Materials Science and Technology, 2018, 34(1): 219-227.
[9]Zeng X H, Xue P, Wu L H, et al. Achieving an ultra-high strength in a low alloyed Al alloy via a special structural design[J]. Materials Science and Engineering A, 2019, 755: 28-36.
[10]Li H, Tang Y, Zeng Z, et al. Effect of ageing time on strength and microstructures of an Al-Cu-Li-Zn-Mg-Mn-Zr alloy[J]. Materials Science and Engineering A, 2008, 498(1-2): 314-320.
[11]Deschamps A, Decreus B, Geuser F, et al. The influence of precipitation on plastic deformation of Al-Cu-Li alloys[J]. Acta Materialia, 2013, 61(11): 4010-4021.
[12]Blankenship C, Starke E. Structure-property relationships in Al-Li-Cu-Mg-Ag-Zr alloy X2095[J]. Acta Metallurgica et Materialia, 1994, 42(3): 845-855.
[13]Sankaran K K, Neal J E, Sastry S M L. Effects of second-phase dispersoids on deformation behavior of Al-Li alloys[J]. Metallurgical and Materials Transactions A, 1983, 14(10): 2174-2178.
[14]王志文, 杨荣东, 黄元春, 等. 时效处理对挤压成型2195铝锂合金组织和力学性能的影响[J]. 金属热处理, 2022, 47(9): 6-11.
Wang Zhiwen, Yang Rongdong, Huang Yuanchun, et al. Effect of aging treatment on microstructure and mechanical properties of extruded 2195 Al-Li alloy[J]. Heat Treatment of Metals, 2022, 47(9): 6-11.

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