纳米Al_2O_3颗粒对纯Fe液诱导凝固过程的分子动力学模拟  

Molecular Dynamics Simulation of Induced Solidification Process of Pure Liquid Fe by Al_2O_3 Nanoparticles

作　　者：赖莉珊[1] 吴永全[1] 沈通[1] 张宁[1] 高帅[1] 

机构地区：[1]上海大学上海市现代冶金及材料制备重点实验室,上海200072

出　　处：《物理化学学报》2012年第6期1347-1354,共8页Acta Physico-Chimica Sinica

基　　金：国家自然科学基金(50974083;51174131);国家自然科学基金钢铁联合基金(50774112);上海市青年科技启明星计划(07QA4021);上海市教育委员会科研创新计划(09YZ24)资助项目~~

摘　　要：采用分子动力学(MD)方法模拟了不同半径大小的纳米Al2O3颗粒夹杂在三个温度下(1750、1730和1710K)对纯Fe液的诱导凝固过程,并分析了作为诱导核心的纳米Al2O3颗粒的结构演变及其对Fe原子体系的凝固过程的影响.发现在诱导过程中,纳米Al2O3颗粒的内部保持较好的晶型结构,仅表面原子有结构变形;诱导凝固的Fe原子主要为面心立方(fcc)和密排六方(hcp)原子;纳米Al2O3颗粒的尺寸越大,发生诱导凝固的温度越高;诱导凝固得到的Fe晶体的晶格取向受纳米Al2O3颗粒在Fe液中的漂移程度影响.The molecular dynamics （MD） method has been used to simulate the solidification process of pure liquid Fe induced by a series of Al2O3 nanoparticles of different radii at three temperatures （1750, 1730 and 1710 K）. The structural evolution of Al2O3 nanoparticles and the effect of these particles on the solidification process of pure Fe have been analyzed. It was found that during the solidification process, the inner structure of the Al2O3 nanoparticles remained crystalline and structural deformation only occurred in surface atoms. The CTIM-2 method showed that the solidified Fe atoms were mainly faced-centered cubic （fcc） and hexagonal closed-packed （hcp） atoms. In addition, the temperature at which solidification took place was influenced by the size of the Al2O3 nanoparticles. The orientations of the resulting Fe crystals were influenced by the extent of the drift of the Al2O3 nanoparticles.

关 键 词：诱导凝固 纳米Al2O3颗粒 纯Fe液 分子动力学模拟 

分 类 号：TB383.1[一般工业技术—材料科学与工程]