The work aims to investigate the effects and mechanisms of different refiners on the grain size of AM50 magnesium alloy, analyze the lattice matching relationship between various elements and the magnesium matrix, further discuss the grain refinement mechanisms of different refiners, and provide effective references for the selection of grain refiners for magnesium alloy. Different modifiers (Al5Ti0.5C, Al5TiB and MgCO3) were added to AM50 magnesium alloy. The microstructure was analyzed and the grain size was statistically measured by Optical Microscopy (OM), X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Energy Dispersive Spectroscopy (EDS). Additionally, an Edge-to-Edge Matching (E2EM) model was employed to calculate the lattice mismatch and atomic mismatch between the nucleating particle phases (Al4C3, Al2CO, TiC and TiB2) in different refiners and α-Mg, so as to analyze the grain refining mechanism. After adding the three refiners of Al5Ti0.5C, Al5TiB and MgCO3, the phase composition of the alloy remained unchanged, but all achieved excellent grain refinement effects. Compared with the AM50 magnesium alloy without refiner treatment, the grain refinement rates reached 87%, 85%, and 80% respectively. Among them, the average grain size of AM50 alloy treated with Al5Ti0.5C decreased from the original 163 μm to 21 μm. In conclusion, all three kinds of refiners (Al5Ti0.5C, Al5TiB, and MgCO3) have good grain refining effects on AM50 alloy, and according to the E2EM model, the Al4C3, Al2CO, TiC and TiB2 particles are all nearly coherent interface relationship with α-Mg in terms of lattice matching, where Al2CO and Mg atom mismatch is the smallest, the alloy with Al5Ti0.5C refiner can provide TiC particles as nucleation core on one hand, and form Al4C3 or Al2CO as nucleation core on the other hand during the densification process, thus demonstrating the optimal grain refinement effect.
Key words
Al5Ti0.5C /
Al5TiB /
MgCO3 /
AM50 magnesium alloy /
refiner
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References
[1] YANG Y, XIONG X M, CHEN J, et al.Research Advances in Magnesium and Magnesium Alloys Worldwide in 2020[J]. Journal of Magnesium and Alloys, 2021, 9(3): 705-747.
[2] ALI Y, QIU D, JIANG B, et al.Current Research Progress in Grain Refinement of Cast Magnesium Alloys: A Review Article[J]. Journal of Alloys and Compounds, 2015, 619: 639-651.
[3] YANG J X, KOONS G L, CHENG G, et al.A Review on the Exploitation of Biodegradable Magnesium-Based Composites for Medical Applications[J]. Biomedical Materials, 2018, 13(2): 022001.
[4] 王珵. 合金元素对镁层错能和孪晶偏析能的影响规律及作用机制[D]. 长春: 吉林大学, 2015.
WANG C.Influence Law and Mechanism of Alloying Elements on Magnesium Layer Dislocation Energy and Twinning Polarization Energy[D]. Changchun: Jilin University, 2015.
[5] LIAO H B, ZHAN M Y, LI C B, et al.Grain Refinement of Mg-Al Alloys Inoculated by MgAl2O4 Powder[J]. Journal of Magnesium and Alloys, 2021, 9(4): 1211-1219.
[6] KOIKE J.Enhanced Deformation Mechanisms by Anisotropic Plasticity in Polycrystalline Mg Alloys at Room Temperature[J]. Metallurgical and Materials Transactions A, 2005, 36(7): 1689-1696.
[7] 张庭凤. 压铸工艺对AM60B镁合金组织和性能的影响[D]. 兰州: 兰州理工大学, 2007.
ZHANG T F.Influence of Die-casting Process on the Organization and Properties of AM60B Magnesium Alloy[D]. Lanzhou: Lanzhou University of Technology, 2007.
[8] 郭成伟. 压铸镁合金AM50的组织和力学性能[D]. 长春: 吉林大学, 2015.
GUO C W.Organization and Mechanical Properties of Die-cast Magnesium Alloy AM50[D]. Changchun: Jilin University, 2015.
[9] PRASAD S V S, PRASAD S B, VERMA K, et al. The Role and Significance of Magnesium in Modern Day Research-a Review[J]. Journal of Magnesium and Alloys, 2022, 10(1): 1-61.
[10] 吴国华, 童鑫, 蒋锐, 等. 铸造Mg-RE合金晶粒细化行为研究现状与展望[J]. 金属学报, 2022, 58(4): 385-399.
WU G H, TONG X, JIANG R, et al.Grain Refinement of As-Cast Mg-RE Alloys: Research Progress and Future Prospect[J]. Acta Metallurgica Sinica, 2022, 58(4): 385-399.
[11] 刘娇龙, 陈海燕, 陈小军, 等. Ti元素对Al-5Mg合金晶粒细化机理研究[J]. 铸造技术, 2024, 45(9): 865-872.
LIU J L, CHEN H Y, CHEN X J, et al.Investigation of the Grain Refinement Mechanism of Ti in Al-5Mg Alloy[J]. Foundry Technology, 2024, 45(9): 865-872.
[12] WANG S, PAN H C, XIE D S, et al.Grain Refinement and Strength Enhancement in Mg Wrought Alloys: A Review[J]. Journal of Magnesium and Alloys, 2023, 11(11): 4128-4145.
[13] 刘艳辉, 毛红奎, 郝晓宇, 等. 铸造镁合金晶粒细化技术的研究进展[J]. 热加工工艺, 2017, 46(3): 19-21.
LIU Y H, MAO H K, HAO X Y, et al.Research Progress on Grain Refinement Technology of Cast Magnesium Alloy[J]. Hot Working Technology, 2017, 46(3): 19-21.
[14] 张玲, 李英龙. 镁合金晶粒细化方法研究进展[J]. 铸造, 2019, 68(11): 1195-1203.
ZHANG L, LI Y L.Research Progress on Grain Refining Methods of Magnesium Alloy[J]. Foundry, 2019, 68(11): 1195-1203.
[15] 李小科. Mg-Al系镁合金的晶粒细化工艺与机理研究[D]. 重庆: 重庆大学, 2011.
LI X K.Study on Grain Refinement Process and Mechanism of Mg-Al Magnesium Alloy[D]. Chongqing: Chongqing University, 2011.
[16] 刘倩, 唐靖林. 碳对镁铝合金晶粒细化影响的研究[J]. 铸造技术, 2008, 29(11): 1498-1502.
LIU Q, TANG J L.Influence of Carbon Addition on Grain Refinement of Magnesium-Aluminum Alloys[J]. Foundry Technology, 2008, 29(11): 1498-1502.
[17] QIAN M, CAO P.Discussions on Grain Refinement of Magnesium Alloys by Carbon Inoculation[J]. Scripta Materialia, 2005, 52(5): 415-419.
[18] 胡中潮, 高忠玉, 陈湖演, 等. Mg-Al合金晶粒细化综述及未来展望[J]. 有色金属加工, 2022, 51(1): 15-20.
HU Z C, GAO Z Y, CHEN H Y, et al.Review and Prospect of Mg-Al Alloy Grain Refinement[J]. Nonferrous Metals Processing, 2022, 51(1): 15-20.
[19] 华溪如, 董喜旺, 吴海, 等. 低成本铸造镁合金研究现状及展望[J]. 精密成形工程, 2025, 17(12): 73-84.
HUA X R, DONG X W, WU H, et al.Research Status and Prospects of Low-cost Cast Magnesium Alloys[J]. Journal of Netshape Forming Engineering, 2025, 17(12): 73-84.
[20] 范文学. Al-Ti-C-Gd中间合金对AZ31的细化作用研究[D]. 大连: 大连理工大学, 2019.
FAN W X.The effect of Al-Ti-C-Gd master alloy on grain refinement of AZ31[D]. Dalian: Dalian University of Technology, 2019.
[21] YE H Z, LIU X Y.Review of Recent Studies in Magnesium Matrix Composites[J]. Journal of Materials Science, 2004, 39(20): 6153-6171.
[22] BRAMFITT B L.The Effect of Carbide and Nitride Additions on the Heterogeneous Nucleation Behavior of Liquid Iron[J]. Metallurgical Transactions, 1970, 1(7): 1987-1995.
[23] ZHANG M X, KELLY P M.Edge-to-Edge Matching and Its Applications[J]. Acta Materialia, 2005, 53(4): 1073-1084.
[24] ZHANG M X, KELLY P M.Edge-to-Edge Matching and Its Applications Part I. Application to the Simple HCP/BCC System[J]. Acta Materialia, 2005, 53(4): 1073-1084.
[25] ZHANG M X, KELLY P M.Edge-to-Edge Matching Model for Predicting Orientation Relationships and Habit Planes—The Improvements[J]. Scripta Materialia, 2005, 52(10): 963-968.
[26] 刘瑞, 徐瑞. 镁合金晶粒异质形核的细化方法[J]. 中国冶金, 2017, 27(8): 6-10.
LIU R, XU R.Heterogeneous Nucleation Grain Refinement Methods for Magnesium Alloy[J]. China Metallurgy, 2017, 27(8): 6-10.
[27] ZHANG M X, KELLY P M, EASTON M A, et al.Crystallographic Study of Grain Refinement in Aluminum Alloys Using the Edge-to-Edge Matching Model[J]. Acta Materialia, 2005, 53(5): 1427-1438.
Funding
Science and Technological Research Program of Chongqing Municipal Education Commission (KJZD-K202201108, KJQN202201160); Chongqing Academicians in Chongqing to Lead the Scientific and Technological Innovation Guidance Special Program (CSTB2023YSZX-JCX0006); Chongqing Natural Science Foundation (CSTB2024NSCQ-MSX0574)
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