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Acta Metall Sin  2019, Vol. 55 Issue (7): 831-839    DOI: 10.11900/0412.1961.2018.00450
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Solidification of Al-Bi Alloy and Influence of Microalloying Element Sn
Wang LI1,2,Qian SUN1,2,Hongxiang JIANG1,Jiuzhou ZHAO1,2()
1. Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
2. School of Materials Science and Engineering, University of Science and Technology of China, Shenyang 110016, China
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Abstract  

Al-Bi alloy has a low friction coefficient and high wear-resistant properties and is a good self-lubricating material for advanced bearings in automotive applications if the soft Bi-rich phase is dispersedly distributed in the comparatively harder Al-based matrix. However, Al-Bi alloy is a typical immiscible alloy. When cooling a homogeneous single phase liquid of Al-Bi alloy in the miscibility gap, it transforms into two liquids. The liquid-liquid phase transformation generally leads to the formation of a phase segregated microstructure. In the last decades, considerable efforts have been made to study the solidification behavior of Al-Bi alloy. It is demonstrated that the microstructure evolution during the liquid-liquid decomposition is a result of concurrent actions of the nucleation, growth, Ostwald ripening and motions of the Bi-rich droplets. The nucleation and the immigration of the Bi-rich droplets show a dominant influence on the solidification microstructure of Al-Bi alloy. Enhancing the nucleation rate and reducing the Marangoni migration velocity of the Bi-rich droplets promote the formation of a well dispersed microstructure. Considering that addition of surface active element to the alloy may result in a reduction in the liquid-liquid interface energy, and thus reduce the nucleation energy barrier and Marangoni migration velocity of the Bi-rich droplets, the possibility to control the solidification process and microstructure of Al-Bi alloys by adding micro-alloying element Sn was investigated. The experimental results show that microalloying element Sn can cause an effective refinement of the Bi-rich particles. The refining effect increases with the increase of Bi content up to 0.10%Sn (mass fraciton). A model was developed to calculate the microstructure formation. The numerical results demonstrate that Sn can act as an effective surface active element for Al-Bi alloys and promote the formation of a well dispersed microstructure.

Key words:  Al-Bi alloy      solidification      microalloying      interfacial energy      simulation     
Received:  25 September 2018     
ZTFLH:  TG111.4,TG27  
Fund: National Natural Science Foundation of China(Nos.51471173);National Natural Science Foundation of China(51771210);National Natural Science Foundation of China(51501207);National Natural Science Foundation of China(China Manned Space Engineering Project)
Corresponding Authors:  Jiuzhou ZHAO     E-mail:  jzzhao@imr.ac.cn

Cite this article: 

Wang LI,Qian SUN,Hongxiang JIANG,Jiuzhou ZHAO. Solidification of Al-Bi Alloy and Influence of Microalloying Element Sn. Acta Metall Sin, 2019, 55(7): 831-839.

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https://www.ams.org.cn/EN/10.11900/0412.1961.2018.00450     OR     https://www.ams.org.cn/EN/Y2019/V55/I7/831

Fig.1  Temperature curve of Al-9.0%Bi alloy during cooling (t—cooling time, tα-Al—growth time of α-Al)
Fig.2  Microstructures of the Al-xBi alloys with x=5.0% (a), x=7.0% (b), x=9.0% (c) and x=12.0% (d)
Fig.3  2D size distributions of the Bi-rich particles in the Al-xBi alloys with x=5.0% (a), x=7.0% (b), x=9.0% (c) and x=12.0% (d)
Fig.4  Microstructures of Al-9.0%Bi-ySn alloys with y=0 (a), y=0.05% (b), y=0.10% (c) and y=0.15% (d)
Fig.6  Microstructures of the Al-xBi-0.10%Sn alloys with x=5.0% (a), x=7.0% (b), x=9.0% (c) and x=12.0% (d)
Fig.7  Average 2D diameters of the Bi-rich particles in the Al-xBi-ySn (y=0, 0.10%) alloys vs Bi content
Fig.5  Average 2D diameters of the Bi-rich particles in the Al-9.0%Bi-ySn alloys with different additions of Sn
Fig.8  Measured distribution of the volume fraction of minority phase particles (MPPs) (?p) in the Al-9.0%Bi alloy along the axial z direction (a) and radial r direction (b)
Fig.9  Measured temperature (Tmelt), equilibrium bimodal line temperature (Tb), undercooling (ΔTd=Tb-Tmelt) of the matrix melt, nucleation rate of the Bi-rich droplets (Id) and the volume fraction of α-Al (ξα-Al) as a function of time during a cooling of the Al-9.0%Bi alloy (dash line) and Al-9.0%Bi-0.10%Sn alloy (solid line). The inserted figure is the enlargement of the microstructure evolution during the period from 3.47 s to 3.55 s. The subscripts 1 and 2 represent the primary droplets and the secondary droplets, respectively
Fig.10  2D average diameters (<Dd>), number density (Nd) and Id of the Bi-rich droplets as a function of time during a cooling of the Al-9.0%Bi alloy (dash line) and Al-9.0%Bi-0.10%Sn alloy (solid line) (The subscripts 1 and 2 represent the primary droplets and the secondary droplets, respectively)
[1] Freitas E S, Silva A P, Spinelli J E, et al. Inter-relation of microstructural features and dry sliding wear behavior of monotectic Al-Bi and Al-Pb alloys [J]. Tribol. Lett., 2014, 55: 111
[2] Ratke L, Diefenbach S. Liquid immiscible alloys [J]. Mater. Sci. Eng., 1995, R15: 263
[3] Zhao J Z, Jiang H X, Sun Q, et al. Progress of research on solidification process and microstructure control of immiscible alloys [J]. Mater. China, 2017, 36: 252
[3] (赵九洲, 江鸿翔, 孙 倩等. 偏晶合金凝固过程及凝固组织控制方法研究进展 [J]. 中国材料进展, 2017, 36: 252)
[4] Zhao J Z, Jiang H X. Progress in the solidification of monotectic alloys [J]. Acta Metall. Sin., 2018, 54: 682
[4] (赵九洲, 江鸿翔. 偏晶合金凝固过程研究进展 [J]. 金属学报, 2018, 54: 682)
[5] Lu W Q, Zhang S G, Zhang W, et al. A full view of the segregation evolution in Al-Bi immiscible alloy [J]. Metall. Mater. Trans., 2017, 48A: 2701
[6] Lu W Q, Zhang S G, Zhang W, et al. Direct observation of the segregation driven by bubble evolution and liquid phase separation in Al-10 wt.% Bi immiscible alloy [J]. Scr. Mater., 2015, 102: 19
[7] Lu W Q, Zhang S G, Li J G. Segregation driven by collision and coagulation of minor droplets in Al-Bi immiscible alloys under aerodynamic levitation condition [J]. Mater. Lett., 2013, 107: 340
[8] Silva A P, Spinelli J E, Mangelinck-No?l N, et al. Microstructural development during transient directional solidification of hypermonotectic Al-Bi alloys [J]. Mater. Des., 2010, 31: 4584
[9] Jia P, Zhang J Y, Geng H R, et al. High-efficiency inhibition of gravity segregation in Al-Bi immiscible alloys by adding Lanthanum [J]. Met. Mater. Int., 2018, 24: 1262
[10] Man T N, Zhang L, Xu N K, et al. Effect of rare-earth Ce on macrosegregation in Al-Bi immiscible alloys [J]. Metals, 2016, 6: 177
[11] Silva A P, Spinelli J E, Garcia A. Microstructural evolution during upward and downward transient directional solidification of hypomonotectic and monotectic Al-Bi alloys [J]. J. Alloys Compd., 2009, 480: 485
[12] Zha M, Li Y J, Mathiesen R H, et al. Dispersion of soft Bi particles and grain refinement of matrix in an Al-Bi alloy by equal channel angular pressing [J]. J. Alloys Compd., 2014, 605: 131
[13] Kang Z Q, Zhang Y B, Yang X, et al. Distribution law of rich Bi phase in Al-Bi monotectic alloy during the solidification process [J]. Mater. Rev., 2018, 32: 598
[13] (康智强, 张煜博, 杨 雪等. Al-Bi过偏晶合金凝固过程中富Bi相分布规律研究 [J]. 材料导报, 2018, 32: 598)
[14] Wu Y Q, Li C J. Investigation of the phase separation of Al-Bi immiscible alloy melts by viscosity measurements [J]. J. Appl. Phys., 2012, 111: 073521
[15] Zhang H W, Xian A P. Study of Al-Bi immiscible alloy controlcasting technique [J]. Acta Metall. Sin., 1999, 35: 1187
[15] (张宏闻, 冼爱平. Al-Bi偏晶合金的控制铸造技术探索 [J]. 金属学报, 1999, 35: 1187)
[16] He J, Zhao J Z, Wang X F, et al. An experimental study of the rapid continuous solidification of Al-Bi immiscible alloy [J]. Acta Metall. Sin., 2006, 42: 67
[16] (何 杰, 赵九洲, 王晓峰等. Al-Bi难混溶合金快速连续凝固的实验研究 [J]. 金属学报, 2006, 42: 67)
[17] Phanikumar G, Dutta P, Galun R, et al. Microstructural evolution during remelting of laser surface alloyed hyper-monotectic Al-Bi alloy [J]. Mater. Sci. Eng., 2004, A371: 91
[18] Zhang H W, Xian A P. Effect of the third element on the structure of casting Al-Bi immiscible alloys [J]. Acta Metall. Sin., 2000, 36: 347
[18] (张宏闻, 冼爱平. 第三组元对Al-Bi偏晶合金凝固组织的影响 [J]. 金属学报, 2000, 36: 347)
[19] Silva A P, Spinelli J E, Garcia A. Thermal parameters and microstructure during transient directional solidification of a monotectic Al-Bi alloy [J]. J. Alloys Compd., 2009, 475: 347
[20] He J, Zhao J Z, Wang X F, et al. Investigation of rapid directional solidification of Al-based immiscible alloys Ⅲ. Effect of the third element [J]. Acta Metall. Sin., 2007, 43: 573
[20] (何 杰, 赵九洲, 王晓峰等. Al基难混溶合金快速定向凝固研究Ⅲ. 第三组元的影响 [J]. 金属学报, 2007, 43: 573)
[21] Zhu J, Wang T M, Cao F, et al. Real-time observation on evolution of droplets morphology affected by electric current pulse in Al-Bi immiscible alloy [J]. J. Mater. Eng. Perform., 2013, 22: 1319
[22] He J, Zhao J Z, Wang X F, et al. Investigation of rapid directional solidification of Al-based immiscible alloys Ⅱ. Effect of static magnetic field [J]. Acta Metall. Sin., 2007, 43: 567
[22] (何 杰, 赵九洲, 王晓峰等. Al基难混溶合金快速定向凝固研究Ⅱ. 恒定磁场的影响 [J]. 金属学报, 2007, 43: 567)
[23] Huang Q, Luo X H, Li Y Y. An alloy solidification experiment conducted on Shenzhou spacecraft [J]. Adv. Space Res., 2005, 36: 86
[24] Yang Z Z, Sun Q, Zhao J Z. Directional solidification of monotectic composition Al-Bi alloy [J]. Acta Metall. Sin., 2014, 50: 25
[24] (杨志增, 孙 倩, 赵九洲. Al-Bi偏晶点成分合金定向凝固过程研究 [J]. 金属学报, 2014, 50: 25)
[25] Lu W Q, Zhang S G, Hu Q D, et al. Interaction between L2 droplets and L1/L interface in solidifying Al-Bi immiscible alloy [J]. Mater. Lett., 2016, 182: 351
[26] Sun Q, Jiang H X, Zhao J Z, et al. Microstructure evolution during the liquid-liquid phase transformation of Al-Bi alloys under the effect of TiC particles [J]. Acta Mater., 2017, 129: 321
[27] Zhao J Z, Ratke L. A model describing the microstructure evolution during a cooling of immiscible alloys in the miscibility gap [J]. Scr. Mater., 2004, 50: 543
[28] Zhao J Z, Li H L, Zhang X F, et al. Nucleation determined microstructure formation in immiscible alloys [J]. Mater. Lett., 2008, 62: 3779
[29] Wu M H, Ludwig A, Ratke L. Modeling of marangoni-induced droplet motion and melt convection during solidification of hypermonotectic alloys [J]. Metall. Mater. Trans., 2003, 34A: 3009
[30] Sun Q, Jiang H X, Zhao J Z. Effect of micro-alloying element Bi on solidification and microstructure of Al-Pb alloy [J]. Acta Metall. Sin., 2016, 52: 497
[30] (孙 倩, 江鸿翔, 赵九洲. 微量元素Bi对Al-Pb合金凝固过程及显微组织的影响 [J]. 金属学报, 2016, 52: 497)
[31] Wang C P, Liu X J, Ohnuma I, et al. Formation of immiscible alloy powders with egg-type microstructure [J]. Science, 2002, 297: 990
[32] Li H L, Zhao J Z, Zhang Q X, et al. Microstructure formation in a directionally solidified immiscible alloy [J]. Metall. Mater. Trans., 2008, 39A: 3308
[33] Zhao L, Zhao J Z. Microstructure formation in a gas-atomized drop of Al-Pb-Sn immiscible alloy [J]. Metall. Mater. Trans., 2012, 43A: 5019
[34] Christian J W. The Theory of Transformations in Metals and Alloys [M]. Amsterdam: Pergamon Press Ltd, 2002: 546
[35] Budai I, Benk? M Z, Kaptay G. Comparison of different theoretical models to experimental data on viscosity of binary liquid alloys [J]. Mater. Sci. Forum, 2007, 537-538: 489
[36] Kaptay G. A new theoretical equation for temperature dependent self-diffusion coefficients of pure liquid metals [J]. Int. J. Mat. Res., 2008, 99: 14
[37] Kaban I, K?hler M, Ratke L, et al. Interfacial tension, wetting and nucleation in Al-Bi and Al-Pb monotectic alloys [J]. Acta Mater., 2011, 59: 6880
[38] He J. Formation mechanism of microstructure in rapidly solidified immiscible alloys [D]. Shenyang: Institute of Metal Research, Chinese Academy of Sciences, 2006
[38] (何 杰. 快速冷却条件下难混溶合金凝固组织形成机理 [D]. 沈阳: 中国科学院金属研究所, 2006)
[39] Yang S, Liu W J, Jia J. Directional solidification of Al-3.4wt%Bi monotectic alloy [J]. Prog. Nat. Sci., 2001, 11: 729
[39] (杨 森, 刘文今, 贾 均. Al-3.4wt%Bi偏晶合金定向凝固组织演变规律研究 [J]. 自然科学进展, 2001, 11: 729)
[40] Jin G. Surfactant Chemistry [M]. Hefei: University of Science and Technology of China Press, 2008: 59
[40] (金 谷. 表面活性剂化学 [M]. 合肥: 中国科学技术大学出版社, 2008: 59)
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