冲击诱导金属铝表面微射流现象的微观模拟  

Microscopic simulation on shock-induced micro-jet ejection from metal Al surface

作　　者：邵建立[1] 王裴[1] 何安民[1] 秦承森[1] 

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,北京100094

出　　处：《物理学报》2012年第18期288-294,共7页Acta Physica Sinica

基　　金：中国工程物理研究院科学技术发展基金(批准号:2009A0101007)资助的课题~~

摘　　要：采用嵌入原子势分子动力学模拟方法,研究了金属铝表面沟槽在冲击下形成微射流的微观过程和动力学性质.通过对模拟结果的统计分析,获得了较宽冲击压力范围内微射流形态的变化规律,以及相应的质量-空间分布和质量-速度分布变化.基于原子中心对称参数,分析了样品近表面非晶态转变和卸载熔化过程,获得了卸载熔化对微射流质量及其分布的影响规律.研究还发现:样品熔化之前,微射流质量与波后粒子速度呈线性增加关系;卸载熔化出现后,微射流质量开始迅速增加;当卸载熔化速度足够快时,金属强度效应可忽略,此时微射流质量与波后粒子速度再次表现出线性增加关系.Via molecular dynamics simulations employing an embedded-atom-method potential, we investigate the microscopic process and dynamical properties of shock-induced micro-jet from a grooved aluminum surface. For a large range of shock pressure, we obtain the micro-jet morphology variation, its mass spatial distribution and mass-velocity distribution. The amorphous state and release melting during the jetting are both analyzed using the central symmetry parameter, where the effect law of release melting on the micro-jet is obtained. It is found that the micro-jet mass keeps a linear increase with the piston velocity prior to release melting; the micro-jet mass is enhanced evidently after release melting; while the velocity of release melting is above a threshold, the jetting mass shows a linear increase with the piston velocity again, where the strength of material can be neglected.

关 键 词：微射流 分子动力学 冲击 

分 类 号：TG146.21[一般工业技术—材料科学与工程]