Effect of Ce on microstructure and thermal conductivity of as-cast Mg-6Zn alloy
DAI Xiao-teng1, MA Ming-long1, ZHANG Kui1, LI Yong-jun1, YUAN Jia-wei1, LIU Xiao-dao2, WANG Sheng-qing2
1. State Key Laboratory of Nonferrous Metals and Processes, GRIMAT Engineering Institute Co., Ltd., Beijing 101499, China;
2. Nanjing Yunhai Special Metals Co., Ltd., Nanjing 211224, China
Abstract：The microstructure of as-cast Mg-6Zn-xCe alloy was investigated by optical microscope (OM), X-ray diffraction (XRD), scanning election microscopy (SEM), energy dispersive spectrometer (EDS), transmission electron microscopy (TEM)and the changing rule of thermal conductivity with the content of Ce was investigated using the flash method. The results show that Mg-6Zn alloy is mainly composed of α-Mg and Mg7Zn3 phases. The ternary phase Ce5 (Mg,Zn)41 which is mainly distributed between grain boundaries and dendrites appears in the alloy after the addition of the rare earth element Ce, and the appearance of ternary phase has an inhibitory effect on Mg7Zn3 phase. The content of eutectic structure is increased by the addition of Ce, and the distribution continuity is improved with the increase of Ce content. The thermal conductivity of the alloy is decreased with the increase of Ce content, which may be caused by the increase of volume fraction, more continuous distribution of eutectic structure in the alloy, the enhanced electron scattering, the extended electron conduction paths and the increased thermal resistance, ultimately the thermal conductivity of the alloy is reduced.
代晓腾, 马鸣龙, 张奎, 李永军, 袁家伟, 刘小稻, 王胜青. Ce对铸态Mg-6Zn合金组织与导热性能的影响[J]. 材料工程, 2020, 48(1): 92-97.
DAI Xiao-teng, MA Ming-long, ZHANG Kui, LI Yong-jun, YUAN Jia-wei, LIU Xiao-dao, WANG Sheng-qing. Effect of Ce on microstructure and thermal conductivity of as-cast Mg-6Zn alloy. Journal of Materials Engineering, 2020, 48(1): 92-97.
[1] 曾小勤,史枭颖.稀土镁合金强韧性设计与开发[J].航空材料学报,2017,37(1):18-25. ZENG X Q,SHI X Y.Strengthening and toughening design and development of Mg-rare earth alloys[J].Journal of Aeronautical Materials,2017,37(1):18-25.
[2] 袁杰,郭宝会.Mg合金在汽车工业中的应用进展[J].铸造技术,2017,38(12):2799-2804. YUAN J,GUO B H.Research advances of magnesium alloys in automobile applications[J].Foundry Technology,2017,38(12):2799-2804.
[3] 王群,王婧超,李雄魁,等.航天用轻质结构材料研究进展及应用需求[J].宇航材料工艺,2017,47(1):1-4. WANG Q,WANG J C,LI X K,et al.Research progress and application requirements of lightweight structure materials for aerospace applications[J].Aerospace Materials & Technology,2017,47(1):1-4.
[4] 王荣贵.镁合金散热器挤压工艺研究[J].中国金属通报,2009(46):42-43. WANG R G. Study on extrusion process of magnesium alloy radiator[J].China Metal Bulletin,2009(46):42-43.
[5] 吴国华,陈玉狮,丁文江.镁合金在航空航天领域研究应用现状与展望[J].载人航天,2016,22(3):281-292. WU G H,CHEN Y S,DING W J.Current research,application and future prospect of magnesium alloys in aerospace industry[J].Manned Spaceflight,2016,22(3):281-292.
[6] LUO A A.Magnesium casting technology for structural applic-ations[J].Journal of Magnesium & Alloys,2013,1(1):2-22.
[7] LEE S,HAM H J,SU Y K,et al.Thermal conductivity of magn-esium alloys in the temperature range from -125℃ to 400℃[J].International Journal of Thermophysics,2013,34(12):2343-2350.
[8] YUAN J W,ZHANG K,LI T,et al.Anisotropy of thermal cond-uctivity and mechanical properties in Mg-5Zn-1Mn alloy[J].Materials & Design,2012,40:257-261.
[9] YING T,ZHENG M Y,LI Z T,et al.Thermal conductivity of as-cast and as-extruded binary Mg-Zn alloys[J].Journal of Alloys & Compounds,2014,608(38):19-24.
[10] 袁家伟.高导热Mg-Zn-Mn合金及其性能研究[D].北京:北京有色金属研究总院,2013. YUAN J W.Study on high thermal conductivity Mg-Zn-Mn alloy and its properties[D].Beijing:General Research Institute for Nonferrous Metals,2013.
[11] YUAN J W,ZHANG K,ZHANG X,et al.Thermal character-istics of Mg-Zn-Mn alloys with high specific strength and high thermal conductivity[J].Journal of Alloys & Compounds,2013,578(6):32-36.
[12] 杨明波,潘复生,李忠盛,等.镁合金铸态晶粒细化技术的研究进展[J].铸造,2005,54(4):314-319. YANG M B,PAN F S,LI Z S,et al.Research and development of the as-cast grain refinement technology of magnesium alloys[J].Foundry,2005,54(4):314-319.
[13] 余琨,黎文献,张世军.Ce对镁及镁合金中晶粒的细化机理[J].稀有金属材料与工程,2005,34(7):1013-1016. YU K,LI W X,ZHANG S J.Mechanism of grain refining by adding cerium in Mg and Mg alloys[J].Rare Metal Materials and Engineering,2005,34(7):1013-1016.
[14] 苏再军,杨树忠,刘楚明,等.Zn对铸态Mg-Y-Nd-Zr合金组织和力学性能的影响[J].材料工程,2017,45(9):116-122. SU Z J,YANG S Z,LIU C M,et al.Effect of Zn on micros-tructure and mechanical properties of as-cast Mg-Y-Nd-Zr alloys[J].Journal of Materials Engineering,2017,45(9):116-122.
[15] LI Q,FAN S,PENG J,et al.Effects of Ce on microstructure and mechanical properties of ZM21 magnesium alloy[J].Materials Research Innovations,2009,18(Suppl 4):178-182.
[16] 吴安如,夏长清.铈含量对ZK60镁合金组织和性能的影响[J].材料热处理学报,2006,27(1):45-48. WU A R,XIA C Q.Effect of cerium content on microstructure and properties of ZK60 magnesium alloy[J].Transactions of Materials and Heat Treatment,2006,27(1):45-48.
[17] 袁家伟,李婷,李兴刚,等.Mg-4Zn-1Mn镁合金均匀化热处理及导热率[J].材料热处理学报,2012,33(4):27-32. YUAN J W,LI T,LI X G,et al.Homogenizing heat treatment and thermal conductivity of Mg-4Zn-1Mn magnesium alloy[J].Transactions of Materials and Heat Treatment,2012,33(4):27-32.
[18] 潘虎成.镁合金导热性能的研究[D].重庆:重庆大学,2013. PAN H C.Study on thermal conductivity of magnesium alloy[D].Chongqing:Chongqing University,2013.
[19] 游国强,白世磊,明玥,等.镁合金导热性能研究进展[J].功能材料,2016,47(5):30-35. YOU G Q, BAI S L, MING Y, et al.Research progress on thermal conductivity of magnesium alloys[J].Journal of Functional Materials,2016,47(5):30-35.
[20] GAO X,NIE J F.Structure and thermal stability of primary intermetallic particles in an Mg-Zn casting alloy[J].Scripta Materialia,2007,57(7):655-658.
2020, Vol. 48 
