压力作用下Al熔体凝固过程的分子动力学模拟研究  

The Crystallization Process of Al Melts under Pressure by Molecular Dynamics Simulations

作　　者：安思敏 高兴誉 刘瑜 孙博[1] 刘海风[1] 宋海峰[1] AN Simin;GAO Xingyu;LIU Yu;SUN Bo;LIU Haifeng;SONG Haifeng(Laboratory of Computational Physics,Institute of Applied Physics and Computational Mathematics,Beijing 100088,China)

机构地区：[1]北京应用物理与计算数学研究所计算物理实验室,北京100088

出　　处：《铸造技术》2023年第2期185-189,共5页Foundry Technology

基　　金：国家自然科学基金(5210011290)。

摘　　要：由于温度和压力不是等效的热力学变量,因此改变压力和温度对结晶过程的影响也是不同的。压力对结晶影响的相关研究仍然不充分。本文采用分子动力学模拟研究了5 GPa下Al熔体在不同温度下的结晶过程,表明该压力下Al熔体的结晶速率随温度的降低而增加,最高可达~125.1 m/s。通过分析晶粒形貌演变过程,揭示了多个晶体取向共存于同一晶粒中的现象,各取向间相互竞争,最终择出优势取向,展现出压力作用下晶粒边长大边进行结构调整的动态演化过程。Since temperature and pressure are not equivalent thermodynamic variables,the effects of changing pressure and temperature on the crystallization process are also different.However,the related research on the influence of pressure on crystallization is far from completed.In this paper,we study the crystallization process of Al melts at different temperatures at 5 GPa using molecular dynamics simulations.We reveal that the crystal growth rates during the crystallization process of Al melts at 5 GPa increase with decreasing temperature,up to~125.1 m/s.We also analyse the atomic mechanism during the crystallization process.Multiple crystal orientations coexist in the same grain.During crystallization,the orientations compete,and finally pressure and temperature select the preferred orientation.

关 键 词：压力 结晶 分子动力学模拟 晶体生长速率 晶体取向 

分 类 号：TG146.21[一般工业技术—材料科学与工程]