Please wait a minute...
 首页  期刊介绍 期刊订阅 联系我们 横山亮次奖 百年刊庆
最新录用  |  预出版  |  当期目录  |  过刊浏览  |  阅读排行  |  下载排行  |  引用排行  |  横山亮次奖  |  百年刊庆
清华大学学报(自然科学版)  2023, Vol. 63 Issue (8): 1297-1308    DOI: 10.16511/j.cnki.qhdxxb.2023.25.012
  论文 本期目录 | 过刊浏览 | 高级检索 |
严泽凡, 刘荣正, 刘兵, 邵友林, 刘马林
清华大学 核能与新能源技术研究院, 北京 100084
Molecular dynamics simulation of sintering behavior of SiC nanocoated particles
YAN Zefan, LIU Rongzheng, LIU Bing, SHAO Youlin, LIU Malin
Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China
全文: PDF(22752 KB)   HTML
输出: BibTeX | EndNote (RIS)      
摘要 碳化硅(SiC)制备在核燃料研究中具有重要意义,例如新型事故容错核燃料采用SiC作为关键基体材料。研究SiC纳米包覆颗粒的烧结行为对优化新型核燃料基体材料制备工艺具有指导意义。该文根据纳米颗粒熔点变化规律,验证了Tersoff势函数进行SiC分子动力学模拟的可行性和模型参数的准确性;考察了纯相SiC、富硅(SiC@Si)和富碳(SiC@C)这3种典型SiC纳米颗粒的烧结演化过程;并对烧结过程进行了定量描述,通过烧结颈生长、能量演变和原子扩散等参量分析了烧结机制,重点关注包覆层结构对SiC烧结行为的影响,从而获得包覆颗粒烧结机理。研究结果表明:包覆层的原子扩散性会促进颗粒原子整体迁移,从而加速整体烧结行为。SiC@Si颗粒比SiC@C颗粒更易发生包覆层原子扩散,因而SiC@Si颗粒更易发生烧结;较低的加热速率在一定程度上有利于烧结进行,但并不影响包覆颗粒的原子扩散模式。研究结果对SiC纳米颗粒烧结机制给出了定量解释,有助于理解SiC烧结制备过程的规律。
E-mail Alert
关键词 碳化硅纳米颗粒烧结包覆层分子动力学模拟    
Abstract:[Objective] The preparation of SiC materials is significant in nuclear fuel research. Presently, SiC materials are applied as a key material in coating layers of tri-structural isotropic (TRISO)-type coated particles and as fully ceramic microencapsulated accident-tolerant fuel (FCM-ATF) matrix materials. The matrix SiC materials of FCM-ATF are sintered from SiC powder or nanoparticles. The SiC nanocoated particles are a kind of important SiC nanoparticles. The study of the sintering behavior of SiC nanocoated particles aims to develop a framework for optimizing the sintering preparation process of the FCM-ATF matrix material.[Methods] In this paper, the melting points of pure SiC nanoparticles of different sizes were first investigated. The feasibility of the Tersoff potential function for molecular dynamics simulations of SiC materials was confirmed using the nanoparticle melting point variation law. Then, the sintering evolution processes of three typical SiC nanoparticles, pure SiC, SiC@Si, and SiC@C, were examined to investigate the influence of the coating layer structure on the sintering behavior of SiC. The sintering process was quantitatively described using variables such as the sintering neck width, atomic number in the neck region, shrinkage ratio, and degree of system densification. The sintering mechanism was described by the ratio of grain boundary energy to surface energy, mean square displacement, atomic displacement vector, and atomic diffusion coefficient.[Results] The study of the structure of SiC nanocoated particles showed that SiC@Si particles were more prone to sintering than SiC@C particles. Vulnerability to sintering was mainly reflected in the faster neck growth and higher densification during the sintering process. The results were closely related to energy evolution and atomic diffusion phenomena. Regarding energy evolution, the grain boundary energy of SiC@Si particles was rapidly converted to surface energy during the sintering process, but the conversion of grain boundary energy to surface energy of SiC@C particles was very slow. According to classical sintering theory, the sintering driving force was mainly provided by the surface energy of the particles. High surface energy catalyzed the surface diffusion of particle atoms during the sintering process. The evidence was corroborated by an analysis of the atomic diffusion aspect. The coating layer had as high surface energy as the surface of the coated particles. Thus, the overall atomic diffusivity of the particles was partially affected by the atomic diffusivity of the coating layer. The overall sintering behavior of the particles was catalyzed by the high atomic diffusivity of the coating layer. The atomic diffusivity of the silicon coating layer was better than that of the carbon coating layer, and the coated layer of the SiC@Si particles was more prone to atomic diffusion than that of the SiC@C particles; hence, sintering and atomic diffusion were more probable in the SiC@Si than in the SiC@C. The study of the heating rate showed that a lower heating rate was somewhat beneficial for sintering but did not affect the atomic diffusion pattern of the coated particle.[Conclusions] The results give a quantitative explanation of the sintering mechanism of SiC nanoparticles. It helps to understand the laws of the SiC sintering preparation process for FCM-ATF matrix materials and also provides a good reference for raw material design, sintering regime, and process optimization of SiC materials preparation.
Key wordssilicon carbide    nanoparticles    sintering    coating layer    molecular dynamic simulation
收稿日期: 2022-10-11      出版日期: 2023-07-22
通讯作者: 刘马林,副教授,      E-mail:
作者简介: 严泽凡(1998-),男,硕士研究生。
严泽凡, 刘荣正, 刘兵, 邵友林, 刘马林. SiC纳米包覆颗粒烧结行为的分子动力学模拟[J]. 清华大学学报(自然科学版), 2023, 63(8): 1297-1308.
YAN Zefan, LIU Rongzheng, LIU Bing, SHAO Youlin, LIU Malin. Molecular dynamics simulation of sintering behavior of SiC nanocoated particles. Journal of Tsinghua University(Science and Technology), 2023, 63(8): 1297-1308.
链接本文:  或
[1] LIU R Z, LIU B, ZHANG K H, et al. High temperature oxidation behavior of SiC coating in TRISO coated particles[J]. Journal of Nuclear Materials, 2014, 453(1-3):107-114.
[2] 史力, 赵加清, 刘兵, 等. 高温气冷堆关键材料技术发展战略[J]. 清华大学学报(自然科学版), 2021, 61(4):270-278. SHI L, ZHAO J Q, LIU B, et al. Development strategy of key materials technology for the high temperature gas-cooled reactor[J]. Journal of Tsinghua University (Science and Technology), 2021, 61(4):270-278. (in Chinese)
[3] TERRANI K A, KIGGANS J O, KATOH Y, et al.Fabrication and characterization of fully ceramic microencapsulatedfuels[J]. Journal of Nuclear Materials, 2012, 426(1-3):268-276.
[4] 陈猛, 陈昭, 刘荣正, 等. 流化床-化学气相沉积颗粒包覆过程数值模拟[J]. 清华大学学报(自然科学版), 2022, 62(10):1645-1659. CHEN M, CHEN Z, LIU R Z, et al. Numerical simulations of particle coating using the fluidized bed-chemical vapor deposition method[J]. Journal of Tsinghua University (Science and Technology), 2022, 62(10):1645-1659. (in Chinese)
[5] RAJU K, YOON D H. Sintering additives for SiC based on the reactivity:A review[J]. Ceramics International, 2016, 42(16):17947-17962.
[6] LIU R Z, LIU M L, CHANG J X. Large-scale synthesis of monodisperse SiC nanoparticles with adjustable size, stoichiometric ratio and properties by fluidized bed chemical vapor deposition[J]. Journal of Nanoparticle Research, 2017, 19(2):26.
[7] ZHAO J, SHI L K, LIU M L, et al. Densification and enhancement of SiC particulate-reinforced fine-grain SiC ceramic[J]. International Journal of Applied Ceramic Technology, 2022, 19(5):2514-2522.
[8] NANDY J, YEDLA N, GUPTA P, et al. Sintering of AlSi10Mg particles in direct metal laser sintering process:A molecular dynamics simulation study[J]. Materials Chemistry and Physics, 2019, 236:121803.
[9] GOUDELI E. Nanoparticle growth, coalescence, and phase change in the gas-phase by molecular dynamics[J]. Current Opinion in Chemical Engineering, 2019, 23:155-163.
[10] LIU C H, ZHU X J, LI X M, et al. Investigation on sintering processes and mechanical properties of Ti-Ta alloys by molecular dynamics simulation[J]. Powder Technology, 2022, 398:117069.
[11] TAVAKOL M, MAHNAMA M, NAGHDABADI R. Shock wave sintering of Al/SiC metal matrix nano-composites:A molecular dynamics study[J]. Computational Materials Science, 2016, 125:255-262.
[12] WU W L, HU Y, MENG X S, et al. Molecular dynamicssimulation of ion-implanted single-crystal 3C-SiC nano-indentation[J]. Journal of Manufacturing Processes, 2022, 79:356-368.
[13] LEE W H, YAO X H, JIAN W R, et al. High-velocity shock compression of SiC via molecular dynamics simulation[J]. Computational Materials Science, 2015, 98:297-303.
[14] DONG X Y, SHIN Y C. Predictions of thermal conductivity and degradation of irradiated SiC/SiC composites by materials-genome-based multiscale modeling[J]. Journal of Nuclear Materials, 2018, 512:268-275.
[15] TERSOFF J. Modeling solid-state chemistry:Interatomic potentials for multicomponent systems[J]. Physical Review B, 1989, 39(8):5566-5568.
[16] STUKOWSKI A. Visualization and analysis of atomistic simulation data with OVITO-the open visualization tool[J]. Modelling and Simulation in Materials Science and Engineering, 2010, 18(1):015012.
[17] THOMPSON A P, AKTULGA H M, BERGER R, et al. LAMMPS:A flexible simulation tool for particle-based materials modeling at the atomic, meso, and continuum scales[J]. Computer Physics Communications, 2022, 271:108171.
[18] SINGH R, SHARMA V. Nano tungsten carbide interactions and mechanical behaviour during sintering:A molecular dynamics study[J]. Computational Materials Science, 2021, 197:110653.
[19] SHIBUTA Y, SUZUKI T. Melting and solidification point of fcc-metal nanoparticles with respect to particle size:A molecular dynamics study[J]. Chemical Physics Letters, 2010, 498(4-6):323-327.
[20] LI K J, KHANNA R, ZHANG J L, et al. Determination of the accuracy and reliability of molecular dynamics simulations in estimating the melting point of iron:Roles of interaction potentials and initial system configurations[J]. Journal of Molecular Liquids, 2019, 290:111204.
[21] MOITRA A, KIM S, KIM S G, et al. Investigation on sintering mechanism of nanoscale tungsten powder based on atomistic simulation[J]. Acta Materialia, 2010, 58(11):3939-3951.
[22] ASORO M A, KOVAR D, SHAO-HORN Y, et al. Coalescence and sintering of Pt nanoparticles:In situ observation by aberration-corrected HAADF STEM[J]. Nanotechnology, 2009, 21(2):025701.
[23] 理查德·莱萨. 计算材料科学导论:原理与应用[M]. 姚曼, 唐葆生, 黄昊, 译. 北京:科学出版社, 2020. LESAR R. Introduction to computational materials science:Fundamentals to applications[M]. YAO M, TANG B S, HUANG H, Trans. Beijing:Science Press, 2020. (in Chinese)
[24] YANG H Y, ZHOU X G, YU J S, et al. Microwave and conventional sintering of the SiC/SiC composites:The densification and pore distributions[J]. Journal of Alloys and Compounds, 2016, 662:252-258.
[25] RIBEIRO S, GÊNOVA L A, RIBEIRO G C, et al. Effect of heating rate on the shrinkage and microstructure of liquid phase sintered SiC ceramics[J]. Ceramics International, 2016, 42(15):17398-17404.
[1] 黄潇立, 陈泽亮, 桂南, 宫厚军, 杨星团, 屠基元, 姜胜耀. 石墨烯强化沸腾传热研究进展及应用综述[J]. 清华大学学报(自然科学版), 2022, 62(10): 1681-1690.
[2] 陈硕, 尤政. 基于AlN/α-SiC的声表面波谐振器应变响应特性[J]. 清华大学学报(自然科学版), 2016, 56(10): 1061-1065.
Full text



版权所有 © 《清华大学学报(自然科学版)》编辑部
本系统由北京玛格泰克科技发展有限公司设计开发 技术支持