铜粉末动态压缩行为的多颗粒有限元分析  

Dynamic Compaction Behaviors of Copper Powders Using Multi-Particle Finite Element Method

作　　者：彭克锋 潘昊[2] 赵凯[1] 郑志军[1] 虞吉林[1] PENG Kefeng;PAN Hao;ZHAO Kai;ZHENG Zhijun;YU Jilin(CAS Key Laboratory of Mechanical Behavior and Design of Materials, Department of Modern Mechanics,University of Science and Technology of China, Hefei 230026, China;Institute of Applied Physics and Computational Mathematics, Beijing 100088, China)

机构地区：[1]中国科学技术大学近代力学系中国科学院材料力学行为和设计重点实验室,安徽合肥230026 [2]北京应用物理与计算数学研究所,北京100088

出　　处：《高压物理学报》2019年第4期72-79,共8页Chinese Journal of High Pressure Physics

基　　金：科学挑战专题(TZ2018001);中央高校基本科研业务费专项资金(WK2480000003)

摘　　要：颗粒金属材料的宏观力学性能与其细观特性密切相关,金属粉末的冲击压缩问题有待深入研究。选用实验结果较为丰富的铜粉末作为研究对象,基于多颗粒有限元法建立了颗粒金属材料的二维数值分析模型,研究了铜粉末在冲击压缩下的力学行为。数值计算结果表明,在较高速度冲击下颗粒金属材料呈现出高度局部化的变形带,变形带如同冲击波一样从冲击端向支撑端传播。利用速度场计算方法,计算得到了塑性冲击波波阵面的位置,进而获得了不同孔隙率(0.25~0.60)铜粉末的粒子速度与冲击波波速之间的 Hugoniot 关系,其在较高冲击速度(200~300 m/s)下与实验结果吻合较好。发展了以动态锁定应变为唯一参数的冲击波模型,较好地表征了铜粉末在较高速度冲击下的 Hugoniot 关系和波后应力。The meso-scale characteristics of granular metal materials play an important role in macroscopic mechanical behavior. The dynamic compression behavior of metal powders still needs further researches. In this paper, the copper powders persisting rich experimental results were selected as the research objects.Based on the multi-particle finite element method, a two-dimensional numerical analysis model of granular metal materials was established, and the mechanical behavior of copper powders under impact compression was studied. The numerical results show that the granular metal materials exhibit a highly localized deformation band under high velocity impact, and the deformation bands propagate from the impact end to the support end like a shock wave. By using the velocity field calculation method, the position of the plastic impact wave front was calculated, and the Hugoniot relationship between the particle velocity and the shock wave velocity of copper powders with different porosities(0.25–0.60) was obtained. The numerical results agree well with the experimental results at high impact velocities(200–300 m/s). The shock wave model using the dynamic locking strain as the only parameter was developed. It is found that the Hugoniot relationship and the stress behind the shock wave front of the copper powders under high velocity impact are well characterized.

关 键 词：颗粒金属材料 冲击压缩 多颗粒有限元法 冲击波模型 HUGONIOT 关系 

分 类 号：O347.5[理学—固体力学]