DYNAMIC CRUSHING OF 2D CELLULAR METALS: MICROSTRUCTURE EFFECTS AND RATE-SENSITIVITY MECHANISMS
The dynamic response of cellular metals has been extensively investigated due to their excellent properties as impact energy absorbers and blast protectors. In the past years, our group focused on charactering the dynamic behavior of 2D cellular metals and achieved much understanding of the microstructural effects on the dynamic mechanical properties and the possible mechanisms governing the rate sensitivity of cellular metals. Three types of microstructural randomness and imperfections were employed in the basic topology model of a regular hexagonal honeycomb. Their influences on deformation mode and plateau stress were studied by finite element method using the ABAQUS/Explicit code. The results show that there are three macroscopic deformation modes occurring when a honeycomb is compressed under different impact velocities. Microstructural randomness and imperfections may strongly affect the energy absorption capacity. The influences of the inertia and the properties of cellwall material on the rate sensitivity of Voronoi honeycombs were explored through numerical tests.The density of cell-wall material was artificially changed to study the influence of inertia, which was found to be the dominant factor in the dynamic crushing of Voronoi honeycombs. The effects of strain hardening and strain-rate hardening of cell-wall materials were examined and found to have minor influence on plateau stress, which cannot explain the strong rate dependence observed in some metal foams.
cellular metals Voronoi honeycomb finite element analysis inertia strain-rate effect
Jilin Yu Zhijun Zheng
CAS Key Laboratory of Mechanical Behavior and Design of Materials, University of Science and Technology of China, Hefei 230027 China
国际会议
广州
英文
45-55
2010-12-17（万方平台首次上网日期，不代表论文的发表时间）