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采用第一性原理分子动力学(Ab Initio Molecular Dynamics,AIMD)方法研究了Al和Zr液固转变过程中的能量、偶关联函数、结构因子和键对分布的变化规律,获得了不同温度下两种金属液体的扩散系数和黏度.结果表明,AIMD计算得到的液态金属偶关联函数、结构因子和扩散系数与实验测量数据符合得很好.在冷速为5.0×1013和2.5×1013K/s时,液态Al分别在730K附近发生玻璃化转变或者形成有一定缺陷的fcc晶体结构.在平均冷却速率为4.3×1013和2.0×1014K/s的条件下,液态Zr在1200K时分别开始转变为热力学上亚稳定的bcc结构和玻璃相.Zr的液态和玻璃态结构中二十面体和bcc类型短程序是其主要拓扑短程序.
The first order principle molecular dynamics (AIMD) method was used to study the variation of energy, even correlation function, structure factor and bond-pair distribution in liquid-solid transformation of Al and Zr. The results show that the liquid metal couple correlation function, structure factor and diffusion coefficient calculated by AIMD are in good agreement with the experimental data.When the cooling rate is 5.0 × 1013 and 2.5 × 1013K / s , And the liquid Al undergoes vitrification or a fcc crystal structure with some defects near 730 K. Under the condition of the average cooling rate of 4.3 × 1013 and 2.0 × 1014K / s, the liquid Zr begins to change into thermodynamics at 1200K Metastable bcc structure and glass phase. The short and long icosahedral and bcc types of short and long forms of Zt in liquid and vitreous structures are the major short-range topologies.