Grain Refinement in an Al-Cu-Li Alloy during Electrically-assisted Recrystallization Annealing

XUE Shaoxi; XU Zhenhai; PENG Heli; SHAN Debin; GUO Bin

doi:10.3969/j.issn.1674-6457.2025.12.013

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Journal of Netshape Forming Engineering ›› 2025, Vol. 17 ›› Issue (12) : 124-132. DOI: 10.3969/j.issn.1674-6457.2025.12.013

Advanced Aerospace Manufacturing Technology

Grain Refinement in an Al-Cu-Li Alloy during Electrically-assisted Recrystallization Annealing

XUE Shaoxi^1,2, XU Zhenhai^3,*, PENG Heli^1,2, SHAN Debin³, GUO Bin³

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Abstract

The work aims to introduce asymmetric rolling and electrically-assisted annealing into the thermomechanical processing of Al-Li alloys for grain refinement, so as to improve microstructural homogeneity and mechanical properties. A four-step process consisting of solution treatment, overaging, asymmetric rolling, and electrically-assisted annealing was applied to investigate the effects of asymmetry ratio and annealing method on grain refinement. Subsequently, the mechanical properties and filling behavior of the alloy were tested. Comparative analysis revealed the distinct positive contributions of both asymmetric rolling and electrically-assisted treatment to grain refinement. Asymmetric rolling introduced shear strain. With asymmetry ratio increasing from 1 to 3, the grain size gradually decreased from 10.44 μm to 7.78 μm, the texture weakened, and the typical shear texture components developed after 90 s of electrically-assisted annealing. Overaging promoted the precipitation of coarse particles, which effectively stimulated nucleation via the particle-stimulated nucleation mechanism. Compared with 1 800 s of conventional annealing, 90 s of electrically-assisted annealing reduced the grain size from 9.90 μm to 7.78 μm when the asymmetry ratio was 3 and promoted a more equiaxed grain morphology. The introduction of the electric current significantly increased the nucleation rate of recrystallization, thereby accelerating grain refinement. The refined grain simultaneously improved strength and plasticity of the alloy. Moreover, it enhanced the uniformity of grain deformation during surface filling, effectively suppressing surface crack formation. The combined use of asymmetric rolling and electrically-assisted annealing effectively refine grains of the 2A97 Al-Li alloy, improve microstructural homogeneity, and enhance overall mechanical properties, showing promising potential for engineering applications.

Key words

Al-Li alloy / electrically-assisted annealing / asymmetric rolling / particles stimulated nucleation / surface texture

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XUE Shaoxi, XU Zhenhai, PENG Heli, SHAN Debin, GUO Bin. Grain Refinement in an Al-Cu-Li Alloy during Electrically-assisted Recrystallization Annealing[J]. Journal of Netshape Forming Engineering. 2025, 17(12): 124-132 https://doi.org/10.3969/j.issn.1674-6457.2025.12.013

References

[1] SONI R, VERMA R, KUMAR G R, et al.A Critical Review of Recent Advances in the Aerospace Materials[J]. Materials Today: Proceedings, 2024, 113: 180-184.
[2] TING Y, JINGHUA J, LISHA W, et al.Overview on the Microstructure and Mechanical Properties of Ultrafine-grained Al-Li Alloys Produced by Severe Plastic Deformation[J]. Rare Metal Materials and Engineering, 2019, 48(1): 55-62.
[3] XU J, WANG X W, WANG C J, et al.A Review on Micro/Nanoforming to Fabricate 3D Metallic Structures[J]. Advanced Materials, 2021, 33(6): 2000893.
[4] WANG J J, XU Z H, XUE S X, et al.A Novel Strategy for Improving the Formability of Surface Arrayed Micro-Grooves by Constructing Dual-Gradient Microstructures[J]. Journal of Materials Processing Technology, 2025, 344: 119049.
[5] KLU E E, JIANG J H, WANG G W, et al.Achieving Ultrahigh Specific Strength of an Ultrafine Grained Mg-9Li-1Al Alloy via the Combined Processing of ECAP with Repeated Annealing and Rolling[J]. Journal of Materials Research and Technology, 2023, 25: 3228-3242.
[6] MAVLYUTOV A M, KIRILENKO D A, LEVIN A A, et al.Superior Strength-Ductility Synergy in Ultrafine-Grained Al-5Mg Alloy[J]. Journal of Materials Research and Technology, 2025, 34: 2329-2343.
[7] WERT J A, PATON N E, HAMILTON C H, et al.Grain Refinement in 7075 Aluminum by Thermomechanical Processing[J]. Metallurgical Transactions A, 1981, 12(7): 1267-1276.
[8] SONG X Y, RETTENMAYR M.Modeling Recrystallization in a Material Containing Fine and Coarse Particles[J]. Computational Materials Science, 2007, 40(2): 234-245.
[9] HUO W T, SHI J T, HOU L G, et al.An Improved Thermo-Mechanical Treatment of High-Strength Al-Zn-Mg-Cu Alloy for Effective Grain Refinement and Ductility Modification[J]. Journal of Materials Processing Technology, 2017, 239: 303-314.
[10] 谢磊. 2A97铝锂合金晶粒细化及超塑性研究[D]. 长沙: 中南大学, 2013: 23-30.
XIE L.Investigation of Grain Refinement and Superplasticity of 2A97Al-Li Alloy[D]. Changsha: Central South University, 2013: 23-30.
[11] DONG H R, LI X Q, LI Y, et al.A Review of Electrically Assisted Heat Treatment and Forming of Aluminum Alloy Sheet[J]. The International Journal of Advanced Manufacturing Technology, 2022, 120(11): 7079-7099.
[12] LI Q, WU M X, XUE L, et al.Overcoming Strength-Ductility Trade-off in Metastable CoCrFeNiAl_0.5 High-Entropy Alloy by an Eco-Friendly Electric Pulse Treatment (EPT)[J]. Journal of Alloys and Compounds, 2025, 1038: 182650.
[13] YANG P H, CHIU M C, HUANG H C, et al.The Behaviors and Mechanisms of Current-Enhanced Recrystallization and Grain Growth in As-Rolled Pure Nickel during Electrical Annealing[J]. Materials Science and Engineering: A, 2025: 149173.
[14] XIAO A, QIN C L, DU X H, et al.The Rebound Suppression and Rapid Solid Solution of Al-Zn-Mg-Cu Alloy under High-Density Electropulsing[J]. Journal of Materials Research and Technology, 2025, 38: 5639-5648.
[15] ZHAO G W, FAN J F, ZHANG H, et al.Exceptional Mechanical Properties of Ultra-Fine Grain AZ31 Alloy by the Combined Processing of ECAP, Rolling and EPT[J]. Materials Science and Engineering: A, 2018, 731: 54-60.
[16] CHEN K, ZHAN L H, ZHANG Y, et al.Effects of Electropulsing Aging on the Mechanical Properties and Microstructure of 7150 Aluminum Alloy[J]. Journal of Alloys and Compounds, 2025, 1010: 177568.
[17] GAO X Y, LIU J, BO L, et al.Achieving Superb Mechanical Properties in CoCrFeNi High-Entropy Alloy Microfibers via Electric Current Treatment[J]. Acta Materialia, 2024, 277: 120203.
[18] 高翔宇, 严仁杰, 张涛, 等. 电脉冲诱导下AZ31镁合金动态再结晶与β-Mg₁₇Al₁₂相低温溶解的协同机制影响[J]. 精密成形工程, 2025, 17(7): 62-68.
GAO X Y, YAN R J, ZHANG T, et al.Synergistic Mechanisms of Electropulsing-Induced Dynamic Recrystallization and Low-Temperature Dissolution of β-Mg₁₇Al₁₂ Phase in AZ31 Magnesium Alloy[J]. Journal of Netshape Forming Engineering, 2025, 17(7): 62-68.
[19] GUO H J, ZENG X, FAN J F, et al.Effect of Electropulsing Treatment on Static Recrystallization Behavior of Cold-Rolled Magnesium Alloy ZK60 with Different Reductions[J]. Journal of Materials Science & Technology, 2019, 35(6): 1113-1120.
[20] LI M H, ZU Y F, CHEN G Q, et al.Ultrafast Recrystallization and Grain Refinement of 2A97 Al-Cu-Li Alloy by Electropulsing Assisted Annealing at Lower Temperature[J]. Journal of Alloys and Compounds, 2024, 1003: 175662.
[21] KIM M J, YOON S, PARK S, et al.Elucidating the Origin of Electroplasticity in Metallic Materials[J]. Applied Materials Today, 2020, 21: 100874.
[22] HUMPHREYS F J, HATHERLY M.Recrystallization and Related Annealing Phenomena[M]. Amsterdam: Elsevier, 2004
[23] CAI G J, HUANG Y R, QING Y Q, et al.Microstructure and Texture Development in (FeCoCrNi)₉₄Al₂Ti₄ Alloy Processed by Asymmetric Hot-Rolling[J]. Journal of Materials Research and Technology, 2025, 34: 2374-2391.
[24] THOME M, HIRT G.Economical and Ecological Benefits of Process-Integrated Surface Structuring[J]. Key Engineering Materials, 2007, 344: 939-946.
[25] 汪鑫伟, 李名扬, 洪秋童, 等. 铝锂合金薄板微结构电流辅助辊压成形工艺研究[J]. 塑性工程学报, 2025, 32(7): 43-58.
WANG X W, LI M Y, HONG Q T, et al.Study on Electrically-Assisted Roll Forming Process of Micro-Texture on Al-Li Alloy Thin Sheet[J]. Journal of Plasticity Engineering, 2025, 32(7): 43-58.
[26] QIN R S, YAN H C, HE G H, et al.Exploration on the Fabrication of Bulk Nanocrystalline Materials by Direct Nanocrystallizing Method I. Nucleation in Disordered Metallic Media by Electropulsing[J]. Chinese Journal of Material Research, 1995, 9: 219-222.
[27] JEONG K, JIN S W, KANG S G, et al.Athermally Enhanced Recrystallization Kinetics of Ultra-Low Carbon Steel via Electric Current Treatment[J]. Acta Materialia, 2022, 232: 117925.
[28] CHEN K, ZHAN L H, YU W F.Rapidly Modifying Microstructure and Mechanical Properties of AA7150 Al Alloy Processed with Electropulsing Treatment[J]. Journal of Materials Science & Technology, 2021, 95: 172-179.