Synergistic Mechanisms of Electropulsing-induced Dynamic Recrystallization and Low-temperature Dissolution of &#x003b2;-Mg17Al12 Phase in AZ31 Magnesium Alloy

GAO Xiangyu; YAN Renjie; ZHANG Tao; WANG Yanyan; GUO Yinglong; ZOU Jinchao

doi:10.3969/j.issn.1674-6457.2025.07.007

PDF(8693 KB)

Journal of Netshape Forming Engineering ›› 2025, Vol. 17 ›› Issue (7) : 62-68. DOI: 10.3969/j.issn.1674-6457.2025.07.007

Composite Material Rolling Technology and Equipment

Synergistic Mechanisms of Electropulsing-induced Dynamic Recrystallization and Low-temperature Dissolution of β-Mg₁₇Al₁₂ Phase in AZ31 Magnesium Alloy

GAO Xiangyu¹, YAN Renjie¹, ZHANG Tao¹, WANG Yanyan², GUO Yinglong¹, ZOU Jinchao^1,*

Author information +

History +

Abstract

The work aims to systematically investigate the effect of electropulsing treatment (EPT) on the microstructural evolution and mechanical properties of rolled AZ31 magnesium alloy. By regulating current density and frequency, combined with metallographic observation, XRD analysis, mechanical testing, and fractography characterization, the synergistic mechanisms of EPT-induced dynamic recrystallization and low-temperature dissolution of the β-Mg₁₇Al₁₂ phase were revealed. The combined effects of Joule heating and electron wind force significantly promoted equiaxed grain refinement. Under optimized parameters (37.5 A/mm², 200 Hz), the grain size was refined from 24.59 μm (as-rolled) to 18.65 μm, accompanied by a 133% increase in elongation and a marginal 7.2% reduction in tensile strength. XRD analysis revealed that the β phase underwent athermal dissolution below 250 ℃. This phenomenon was attributed to the electron wind force driving the diffusion of Al atoms, while the pulsed current-induced dislocation multiplication generated interfacial defects, providing additional diffusion pathways for atoms and thereby promoting the dissolution of the β phase. Fracture morphology transitioned from a mixed brittle-ductile mode to a fully ductile mode, with dimple density and size exhibiting significant optimization as recrystallization progressed. Microhardness testing indicated a gradual decline in hardness with the increasing current density and frequency, which was consistent with reduced dislocation density and enhanced recrystallization. EPT effectively improves the strength-ductility balance of AZ31 alloy through grain refinement, dissolution of brittle phases, and dislocation elimination, offering critical theoretical insights and technical guidance for advancing short-process precision forming technologies in magnesium alloy applications.

Key words

AZ31 magnesium alloy / electropulsing treatment / mechanical properties / microstructural evolution / dislocation multiplication

Cite this article

EndNote

Ris (Procite)

Bibtex

Download Citations

GAO Xiangyu, YAN Renjie, ZHANG Tao, WANG Yanyan, GUO Yinglong, ZOU Jinchao. 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 https://doi.org/10.3969/j.issn.1674-6457.2025.07.007

References

[1] HUANG Z Q, HUANG Q X, WEI J C, et al.Inhibitory Effects of Prefabricated Crown on Edge Crack of Rolled AZ31 Magnesium Alloy Plate[J]. Journal of Materials Processing Technology, 2017, 246: 85-92.
[2] 李忠盛, 潘复生, 张静. AZ31镁合金的研究现状和发展前景[J]. 金属成形工艺, 2004(1): 54-57.
LI Z S, PAN F S, ZHANG J.Present Research Status and Development Prospect of AZ31 Magnesium Alloy[J]. Metal Forming Technology, 2004(1): 54-57.
[3] ZHAO P J, WU Q, YANG Y L, et al.Process Optimization of the Hot Stamping of AZ31 Magnesium Alloy Sheets Based on Response Surface Methodology[J]. Materials, 2023, 16(5): 1867.
[4] 张娜娜, 李全安, 陈晓亚, 等. 变形镁合金织构调控的研究进展[J]. 材料热处理学报, 2024, 45(8): 13-26.
ZHANG N N, LI Q A, CHEN X Y, et al.Research Progress on Texture Control of Wrought Magnesium Alloys[J]. Transactions of Materials and Heat Treatment, 2024, 45(8): 13-26.
[5] WANG T, WANG Y L, BIAN L P, et al.Microstructural Evolution and Mechanical Behavior of Mg/Al Laminated Composite Sheet by Novel Corrugated Rolling and Flat Rolling[J]. Materials Science and Engineering: A, 2019, 765: 138318.
[6] LIU Y H, CHEN Z, HUANG Y, et al.Effect of Cryogenic Treatment on 7A09 Aluminum Alloy and Optimization of Process Parameters[J]. Journal of Materials Engineering and Performance, 2024: 1-15.
[7] MOLNÁR P, JÄGER A. Multi-Temperature Equal Channel Angular Pressing of Mg-3wt%Al-1wt%Zn Alloy[J]. Philosophical Magazine, 2013, 93(27): 3612-3626.
[8] 范爱琴, 周乐育, 邓陈虹, 等. 等通道转角挤压超细晶材料技术及其发展[J]. 钢铁研究学报, 2012, 24(7): 1-4.
FAN A Q, ZHOU L Y, DENG C H, et al.Research and Development of Ultra-Fine Grain Technology with Equal Channel Angular Extrusion Processing[J]. Journal of Iron and Steel Research, 2012, 24(7): 1-4.
[9] CHEN K, ZHAN L H, XU Y Q, et al.Effect of Pulsed Current Density on Creep-Aging Behavior and Microstructure of AA7150 Aluminum Alloy[J]. Journal of Materials Research and Technology, 2020, 9(6): 15433-15441.
[10] GUO J J, WANG F, ZHANG S J, et al.Effect of High-Frequency Electric Pulse on the Solidification Microstructure and Properties of Hypoeutectic Al-Si Alloy[J]. Materials, 2024, 17(2): 468.
[11] XIAO H, XIA X S, HUANG S H, et al.Study on Mechanical Behavior and Microstructure Evolution of Al-Mg-Li Alloy during Electropulsing Assisted Uniaxial Tensile[J]. Journal of Alloys and Compounds, 2022, 900: 163425.
[12] SUN S D, TANG G Y, SONG G L, et al.Multi-pass Thermo-electropulsing Rolling Improved Mechanical Properties of AZ31 Magnesium Alloy Strips[J]. Russian Journal of Physics, 2013, 9: 53-61.
[13] SUN S D, TANG G Y.Influence of Thermo-Electropulsing Rolling Process on Microstructure and Mechanical Properties of AZ31 Magnesium Alloy Strip[J]. Advanced Materials Research, 2013, 744: 375-378.
[14] WEI S, MA P P, CHEN L H, et al.High Density Dislocations Enhance Creep Ageing Response and Mechanical Properties in 2195 Alloy Sheet[J]. Journal of Central South University, 2024, 31(7): 2194-2209.
[15] HAQUE A, SHERBONDY J, WARYWOBA D, et al.Room-Temperature Stress Reduction in Welded Joints through Electropulsing[J]. Journal of Materials Processing Technology, 2022, 299: 117391.
[16] DUTRA J C, RIFFEL K C, SILVA R H G E, et al. A Contribution to the Analysis of the Effects of Pulsed Current in GTAW Welding of 1 mm-Thick AISI 304 Sheets[J]. Metals, 2023, 13(8): 1387.
[17] TANG Z J, AI Y C, XU A J.Investigation into the Local Continuous Heating Calibration Process of a 304 Stainless Steel Pipe by Electrically Assisted Roll Bending[J]. Transactions of the Canadian Society for Mechanical Engineering, 2024, 48(1): 68-74.
[18] WU J W, WANG Z M, ZHU Z G, et al.Effect of Fast-Frequency Pulsed Current Parameters on FFP-TIG Arc Behavior and Its Implications for Inconel 718 Welding[J]. Metals, 2023, 13(5): 848.
[19] NING F K, LE Q C, KONG S P.Effect of Annealing Temperature on Corrosion Properties of Rolled AZ31-Ce Magnesium Alloy[J]. SN Applied Sciences, 2020, 2(4): 762.
[20] ZHANG W Y, ZHANG H, WANG L F, et al.Microstructure Evolution and Mechanical Properties of AZ31 Magnesium Alloy Sheets Prepared by Low-Speed Extrusion with Different Temperature[J]. Crystals, 2020, 10(8): 644.
[21] HUANG Z Q, GUO Y, HUANG R Y, et al.Corrosion and Discharge Behavior of As-Rolled AZ91 Magnesium Alloy after Electro-Pulsing Treatment[J]. Advanced Engineering Materials, 2024, 26(24): 2402026.
[22] YIN F, MA S T, HU S, et al.Understanding the Microstructure Evolution and Mechanical Behavior of Titanium Alloy during Electrically Assisted Plastic Deformation Process[J]. Materials Science and Engineering: A, 2023, 869: 144815.
[23] SONG Y L, WU Y H, LU J, et al.Promoting Dynamic Recrystallization of Al-Zn-Mg-Cu Alloy via Electroshock Treatment[J]. Metals, 2023, 13(5): 944.
[24] 毕广利, 许浩彬, 姜静, 等. 复合加工Mg-Y-Zn-Ni合金的显微组织和性能[J]. 特种铸造及有色合金, 2024, 44(4): 433-440.
BI G L, XU H B, JIANG J, et al.Microstructures and Properties of Mg-Y-Zn-Ni Alloy by Combined Machining[J]. Special Casting & Nonferrous Alloys, 2024, 44(4): 433-440.
[25] TIAN J, DENG J F, SHI Q X, et al.Effect of Temperature Field and Stress Field of Different Crack Behavior on Twins and Dislocations under Mg Alloy Rolling[J]. Materials, 2021, 14(19): 5668.
[26] XU X H, KANG Q X, LIU Y K, et al.Effects of Electropulsing Treatment on the Microstructural Evolution of Hot-Rolled TiBw/TA15 Composite Billet with a Network Architecture[J]. Materials Characterization, 2022, 194: 112341.
[27] VAN IDERSTINE D, MUJAHID S, PAUDEL Y, et al.Effect of Electrical Resistance Heating on Recrystallization of Cold-Rolled Low-Carbon Steel[J]. Crystals, 2023, 13(12): 1650.

Funding

; Fund：The National Natural Science Foundation of China (52204396); Joint Fund Project of the National Natural Science Foundation of China (U24A20119); Scientific Research Startup Fund Project of Taiyuan University of Science and Technology (20222087)