摘要
金属材料在多次强冲击加卸载过程中的复杂动力学行为研究在惯性约束核聚变、冲击防护等领域具有重要的应用价值.多次冲击加载下,材料内部除冲击波与物质相互作用外,还包含首次加载形成的破碎体中颗粒间相互作用,研究三维分布状态已知的疏松材料冲击动态响应将有助于认识该问题.本研究以典型尺度为微米、亚毫米、毫米,初始状态清晰的三种疏松锡为实验样品;采用X光照相、激光干涉测速、可见光高速分幅照相等测试技术;实验观测了10 GPa量级冲击波作用下3种疏松锡的动力学响应.结果显示,激波过后破碎体不能被完全压实,表面产生大量远高于理论自由面速度的喷射物;波后密度、高速喷射物的状态与初始疏松态密切相关.采用SPH方法对实验结果进行了数值模拟分析,揭示了波后材料分布特征及产生高速喷射物的机理.
The dynamic fracture and fragmentation of solid materials subjected to shocks have been widely studied for several decades.Motivations for investigating shock-induced damage behavior are both practical and scientific.In many cases,the loading conditions are two or more continuous shockwaves,causing complex dynamic behavior.Understanding the complex dynamics of metal materials under multiple strong shockwave loadings is important for inertial confinement fusion and impact protection.Under multiple shockwave loadings,the shockwaves not only interact with the material,but also cause interactions among the particles in the porous structure produced by the first impact.These complex dynamics might be revealed by studying the impact response of metals with a clear three-dimensional pore distribution.In this study,experiments were performed on three kinds of porous tin with typical dimensions(millimeters,submillimeters,and micrometers)and a clear initial structure.The dynamic behaviors of the porous tins under a 10 GPaorder shockwave loading were characterized by X-ray images,high-speed photography,and photon Doppler velocimetry.The porous tin was not completely compacted after the shockwave,and many particles were ejected at velocities far exceeding the theoretical free-surface velocity.The post-shockwave material density and status of the high-speed ejection were closely related to the initial structure of the porous tin.The distribution characteristics of the material after the shockwave,and the generation mechanism of the high-speed jets,were determined in numerical simulations.After the shock loading,the surface spray was ejected at high speed and the particles inside the porous stucture collided with each other,also at high speed.The particle collisions in the porous structure contributed significantly to the high-speed ejections and the distribution of material density.This study is significant for understanding the dynamic responses of metal materials under multiple shockwave loadings.
作者
王维荣
李欣竹
陈书杨
吴强
WANG WeiRong;LI Xin Zhu;CHEN ShuYang;WU Qiang(Laboratory for Shockwave and Detonation Physics,Institute of Fluid Physics,China Academy of Engineering Physics,Mianyang 621900,China)
出处
《中国科学：物理学、力学、天文学》
CSCD
北大核心
2020年第10期69-77,共9页
Scientia Sinica Physica,Mechanica & Astronomica
基金
科学挑战专题(编号:TZ2016001)资助项目。
关键词
强冲击
疏松锡
多次冲击加载
shockwave impact
porous tin
multiple shockwave loadings
