强激光加载下锡材料微喷颗粒与气体混合回收实验研究及颗粒度分析  

Experimental investigation of tin fragments mixing with gas subjected to laser driven shock

作　　者：辛建婷[1] 赵永强[1] 储根柏[1] 席涛[1] 税敏[1] 范伟[1] 何卫华[1] 谷渝秋[1] Xin Jian-Ting Zhao Yong-Qiang Chu Gen-Bai Xi Tao Shui Min Fan Wei He Wei-Hua Gu Yu-Qiu(Laboratory of Science and Technology on Plasma Physics, Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900, China)

机构地区：[1]中国工程物理研究院激光聚变研究中心,等离子物理重点实验室,绵阳621900

出　　处：《物理学报》2017年第18期180-185,共6页Acta Physica Sinica

基　　金：等离子体物理重点实验室基金(批准号:9140C680305140C68289)资助的课题~~

摘　　要：冲击波在金属材料自由面卸载时,材料表面会形成微颗粒向外喷射,这是材料表面一种特殊的破坏形态.在内爆压缩和高压工程领域的相关物理过程中,微喷射颗粒是引起界面混合现象的重要来源,会直接影响后期的混合状态和压缩过程.而微颗粒的尺寸、形态、运动速度等是开展微喷混合过程理论和数值模拟研究的重要参数.由于实验中动态诊断的难度较大,目前已获取的微喷颗粒尺寸及分布数据十分有限.基于神光Ⅲ原型激光装置,本文设计并开展了强激光驱动冲击加载,锡材料微喷颗粒经过气体区混合后,低密度泡沫材料对微颗粒进行回收分析的实验研究.通过对微喷颗粒回收样品的X光电子计算机断层扫描分析和图像重建,获得了两个典型加载压强条件下与气体混合后微喷颗粒的三维图像,通过与真空实验条件下回收微喷颗粒图像的对比分析,对混合后的微喷颗粒分布形态有了初步的认识;测量统计了回收颗粒尺寸与数目,并通过分析,给出了微喷颗粒尺寸的双指数分布规律.When a shock wave reflects from the free surface of a solid sample, fragments may be emitted from the surface.Understanding the process of the fragments mixing with gas is an important subject for current researches in inertial confinement fusion and high pressure science. Particularly, obtaining the fragments size and distribution is important for developing or validating the physical fragmentation model. At present, the reported quantitative data are less due to the great challenges in the time-resolved measurements of the fragments.Recently, high-power laser has appeared as a promising shock loading means for fragment investigation. The advantages existing in such means mainly include small sample（～ μm to mm-order）, convenient dynamic diagnosis and soft recovery of fragments. Our group has performed the dynamic fragmentation experiments under laser shock loading metal. The ejected fragments under different loading pressures are softly recovered by low density medium of poly 4-methy1-1-pentene（PMP） foam. The sizes, shapes and penetration depths of the fragments are quantitatively analyzed by X-ray micro-tomography and the improved-watershed method.This paper mainly reports the research advances in the process of the fragments mixing with gas. The laser-driven shock experiments of tin sample are performed at Shenguang-Ⅲ prototype laser facility. Under two typical loading pressures, the fragments mixed with gas（N_2） are recovered by PMP foam with a density of 200 mg/cm^3, and the pressure of gas is 1 atm.The high resolution reconstructed images of the recovered fragments provided by X-ray micro-tomography and computed tomography reconstruction show that the shapes of the fragments are almost homogeneous, and their sizes are in a range of about 1–20 micron. These images are very different from the images of the fragments recovered in vacuum under similar loading pressures. The observed fragments under loading pressure less than 10 GPa in vacuum are some thin layers, while the loading pressure is

关 键 词：强激光 微喷颗粒 气体混合 计算机断层分析 

分 类 号：TG665[金属学及工艺—金属切削加工及机床] TN249[电子电信—物理电子学]