摘要
该文在深入分析闭孔泡沫金属CT扫描图像的基础上,根据其细观结构特点,提出了泡沫金属三维细观模型建模方法。首先,根据闭孔泡沫金属胞孔形状和尺寸分布特性,提出了采用随机椭球体模拟胞孔的建模方法,通过采用随机投放算法,建立了三维胞孔随机投放模型;其次,提出了有限元网格剖分算法,通过引入材料属性识别算法,建立了泡沫金属三维有限元细观模型。在此基础上,研究了冲击荷载下泡沫金属的力学性能,分析了细观损伤破坏机理和能量吸收特性。结果表明,该文建立的三维细观模型,能够较好地反映泡沫金属材料的力学性能和细观损伤破坏机理。
This paper presents a methodology for the development of a three-dimensional mesoscopic model of a closed-cell metallic foam based on the characteristics of mesoscopic structures and CT scan images. Firstly, the distribution of pores of closed-cell metallic foam and their shape and size is analyzed. An ellipsoid with random shape and size is employed to model the pores. The randomly distributed pore model is set up using a random take ＆ place algorithm. Secondly, an algorithm for material property identification is employed in the generation of a finite element model. As a result, the three-dimensional mesoscopic model of metallic foam is set up. On the basis of the mesoscopic model, the mechanical properties of metallic foam under impact loading are investigated numerically. Its energy absorption capability characteristics are simulated. Furthermore, the mechanism of mesoscopic damage for cell-walls is analyzed. Results show that the mesoscopic model presented in this paper can realistically reveal the mechanical properties and mesoscopic damage patterns of a closed-cell metallic foam.
出处
《工程力学》
EI
CSCD
北大核心
2017年第8期212-221,共10页
Engineering Mechanics
基金
侵彻爆炸冲击效应及防护研究项目(51321064)
混凝土多尺度力学模型的建立及高应变速率下损伤破坏机理项目(51478464)
多模式X射线层析成像分析仪研发与应用项目(2014YQ240445)
关键词
泡沫金属
细观模型
椭球体
数值模拟
冲击
metallic foam
mesoscopic model
ellipsoid
numerical simulation
impact
