弥散固态颗粒对Al-Bi合金液-液相分离过程的影响
收稿日期: 2018-07-31
修回日期: 2018-10-14
网络出版日期: 2018-10-22
基金资助
国家自然科学基金项目(51674083);国家自然科学基金项目(50901019);高等学校学科创新引智计划项目(B07015)
Influence of Dispersed Solid Particles on the Liquid-Liquid Separation Process of Al-Bi Alloys
Received date: 2018-07-31
Revised date: 2018-10-14
Online published: 2018-10-22
Supported by
National Natural Science Foundation of China(51674083);National Natural Science Foundation of China(50901019);Programme of Introducing Talents of Discipline to Universities(B07015)
通过向Al-Bi难混溶合金中添加稀土生成CeBi2颗粒，在液淬和自然冷却2种冷却方式下研究固态颗粒对液-液相分离的作用。固态颗粒成为富Bi液滴的形核质点，提高了形核率，促进液滴尺寸细化和弥散分布，进而提高了合金耐磨性能。通过分散粒子法对富Bi液滴的运动、生长和凝并行为进行模拟分析，发现Stokes运动是富Bi液滴宏观偏析的主要成因，熔体自然对流对液滴分布也有一定影响。添加Ce增加了凝固各时间段的富Bi液滴数量，细化液滴尺寸，使液滴运动速度降低。与较快出现宏观偏析的Al-Bi合金相比，Al-Bi-Ce合金中虽然有同样的粗化和偏析趋势，但进行速度相对较慢，宏观偏析较轻。液滴在凝并后期出现了尺寸的多峰分布，峰值随液滴尺寸增加由高向低排列。数值模拟结果与实验统计结果体现了较好的一致性。
张林 , 满田囡 , 王恩刚 . 弥散固态颗粒对Al-Bi合金液-液相分离过程的影响[J]. 金属学报, 2019 , 55(3) : 399 -409 . DOI: 10.11900/0412.1961.2018.00327
Al-Bi alloy is a kind of bearing material with self-lubricating performance. Whereas, in such immiscible alloys macrosegregation occurs generally due to the miscibility gap in solidification process. This study is designed to produce CeBi2 compound particles in Al-Bi melt through the addition of rare earth element Ce. The solidification experiment is processed with liquid quenching and natural cooling respectively, and the effect of dispersive solid particles on liquid-liquid separation is compared at different cooling rate. The dispersive solid particles act as nucleation site and improve the nucleation rate of Bi-rich droplets in liquid-liquid solidification, leading to the size refinement and dispersive distribution of Bi-rich phase, which promote the bearing performance of Al-Bi alloy. The behavior of Bi-rich droplets is simulated by using of discrete multi-particle approach, considering the movement, growth and collision. The results show that Stokes motion is the main cause of macrosegregation, and the natural convection affects the distribution of droplets. The natural convection prolongs the suspension time of droplets, and reduces the macrosegregation. In the case of Ce addition, CeBi2 acts as nucleation site to enhance the amount of Bi-rich particles in each time step of simulation and refine the droplet size, which lead to a reduction of macrosegregation. Compared with the Ce free specimens, Al-Bi-Ce alloy has a slower segregation rate and relatively less macrosegregation. Both the simulation and experiment results show a multimodal particle size distribution, and their peak value decrease with increasing particle size. The simulated results is in good accordance with the experiment.
Key words： immiscible alloy; Al-Bi; Ce; liquid-liquid separation; solid particle
| [1] | Ratke L, Diefenbach S. Liquid immiscible alloys [J]. Mater. Sci. Eng., 1995, R15: 263 |
| [2] | Manasijević D, Minić D, Balanović L, et al. Experimental investigation and thermodynamic prediction of the Al-Bi-In phase diagram [J]. J. Alloys Compd., 2016, 687: 969 |
| [3] | Carlberg T, Fredriksson H. The influence of microgravity on the solidification of Zn-Bi immiscible alloys [J]. Metall. Trans., 1980, 11A: 1665 |
| [4] | Huang Q, Luo X H, Li Y Y. An alloy solidification experiment conducted on Shenzhou spacecraft [J]. Adv. Space Res., 2005, 36: 86 |
| [5] | Andrews J B, Briggs C J, Robinson M B. Containerless low gravity processing of immiscible gold-rhodium alloys [R]. Alabama: Marshall Space Flight Center, 1990 |
| [6] | Wang N, Zhang L, Peng Y L, et al. Composition-dependence of core-shell microstructure formation in monotectic alloys under reduced gravity conditions [J]. J. Alloys Compd., 2016, 663: 379 |
| [7] | Chen S, Zhao J Z. Solidification of monotectic alloy under laser surface treatment conditions [J]. Acta Metall. Sin., 2013, 49: 537 |
| [7] | 陈 书, 赵九洲. 偏晶合金在激光表面处理条件下的凝固行为研究 [J]. 金属学报, 2013, 49: 537 |
| [8] | Li Z Q, Wang W L, Zhai W, et al. Formation mechanism of layered microstructure and monotectic cell within rapidly solidified Fe62.1Sn27.9Si10 alloy [J]. Acta Phys. Sin., 2011, 60: 705 |
| [8] | 李志强, 王伟丽, 翟 薇等. 快速凝固Fe62.1Sn27.9Si10合金的分层组织和偏晶胞形成机理 [J]. 物理学报, 2011, 60: 705 |
| [9] | Wei B, Herlach D M, Sommer F, et al. Rapid solidification of undercooled eutectic and monotectic alloys [J]. Mater. Sci. Eng., 1993, A173: 355 |
| [10] | Luo S B, Wang W L, Chang J, et al. A comparative study of dendritic growth within undercooled liquid pure Fe and Fe50Cu50 alloy [J]. Acta Mater., 2014, 69: 355 |
| [11] | Zhao L, Jiang H X, Ahmad T, et al. Study of solidification for gas-atomized droplet of Cu-Co-Fe alloy [J]. Acta Metall. Sin., 2015, 51: 883 |
| [11] | 赵 雷, 江鸿翔, Ahmad T等. Cu-Co-Fe合金雾化合金液滴凝固过程研究 [J]. 金属学报, 2015, 51: 883 |
| [12] | Zhai W, Liu H M, Zuo P F, et al. Effect of power ultrasound on microstructural characteristics and mechanical properties of Al81.3Sn12.3Cu6.4 monotectic alloy [J]. Prog. Nat. Sci., 2015, 25: 471 |
| [13] | Da D A, Jiang W S, Wang Y M. Process of binary monotectic alloy under simulated microgravity effect by electromagnetic force [J]. Chin. Space Sci. Technol., 1988, 8(6): 20 |
| [13] | 达道安, 姜万顺, 王毓敏. 用电磁力模拟空间微重力效应制备二元偏晶合金 [J]. 中国空间科学技术, 1988, 8(6): 20) |
| [14] | Jiang H X, He J, Zhao J Z. Influence of electric current pulses on the solidification of Cu-Bi-Sn immiscible alloys [J]. Sci. Rep., 2015, 5: 12680 |
| [15] | Zhang L, Wang E G, Zuo X W, et al. Effect of high magnetic field on solidified structure of Cu-80%Pb hypermonotectic alloy [J]. Acta Metall. Sin., 2008, 44: 165 |
| [15] | 张 林, 王恩刚, 左小伟等. 强磁场对Cu-80%Pb过偏晶合金凝固组织的影响 [J]. 金属学报, 2008, 44: 165 |
| [16] | 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 |
| [16] | 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 |
| [17] | Yasuda H, Ohnaka I, Kawakami O, et al. Effect of magnetic field on solidification in Cu-Pb monotectic alloys [J]. ISIJ Int., 2003, 43: 942 |
| [18] | Zhang L, Man T N, Huang M H, et al. Numerical simulation of droplets behavior of Cu-Pb immiscible alloys solidifying under magnetic field [J]. Materials, 2017, 10: 1005 |
| [19] | Kaban I G, Hoyer W. Characteristics of liquid-liquid immiscibility in Al-Bi-Cu, Al-Bi-Si, and Al-Bi-Sn monotectic alloys: Differential scanning calorimetry, interfacial tension, and density difference measurements [J]. Phys. Rev., 2008, 77B: 125426 |
| [20] | 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 |
| [20] | 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 |
| [21] | 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 |
| [21] | 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 |
| [22] | Kaban I, K?hler M, Ratke L, et al. Phase separation in monotectic alloys as a route for liquid state fabrication of composite materials [J]. J. Mater. Sci., 2012, 47: 8360 |
| [23] | Sun Q, Jiang H X, Zhao J Z, et al. Effect of TiC particles on the liquid-liquid decomposition of Al-Pb alloys [J]. Mater. Des., 2016, 91: 361 |
| [24] | 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 |
| [25] | Zhang L, Wang E G, Zuo X W, et al. Effect of magnetic field on liquid-liquid separation of Cu-Pb-La hypermonotectic alloy [J]. Rare Met. Mater. Eng., 2015, 44: 344 |
| [25] | 张 林, 王恩刚, 左小伟等. 磁场对Cu-Pb-La过偏晶合金液-液分离的作用 [J]. 稀有金属材料与工程, 2015, 44: 344 |
| [26] | Nestler B, Wheeler A A, Ratke L, et al. Phase-field model for solidification of a monotectic alloy with convection [J]. Physica, 2000, 141D: 133 |
| [27] | Farjami S, Koyama T, Kainuma R, et al. Phase-field simulation of dragging of liquid Bi particles during the thermally activated migration of grain boundaries in the Al-Bi system [J]. Scr. Mater., 2007, 56: 433 |
| [28] | Ratke L. Coarsening of liquid Al-Pb dispersions under reduced gravity conditions [J]. Mater. Sci. Eng., 1995, A203: 399 |
| [29] | 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 |
| [30] | 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 |
| [31] | Patankar S V. Numerical Heat Transfer and Fluid Flow [M]. New York: Mcgraw-Hill, 1980: 13 |
| [32] | Ratke L, Voorhees P W. Growth and Coarsening: Ostwald Ripening in Materials Processing [M]. Berlin, Heidelberg: Springer, 2002: 242 |
| [33] | Kaptay G. On the temperature gradient induced interfacial gradient force, acting on precipitated liquid droplets in monotectic liquid alloys [J]. Mater. Sci. Forum, 2006, 508: 269 |
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