【摘要】 高孔隙率泡沫金属材料由于其较长的应力平台可以吸收较多的能量,在结构耐撞性设计中有重要的应用前景。然而,实验研究表明当高孔隙率泡沫金属材料承受强冲击载荷时,可能发生应力/力增强现象,从而对被保护结构造成较严重的损伤。采用二维Voronoi随机分布模型研究"真实"泡沫材料在不同持时的强冲击载荷作用下可能出现的力/应力增强现象。对5种不规则的泡沫金属材料计算结果表明:在强冲击载荷达到一定强度时,在泡沫金属材料中应力/力传递会出现应力/力的增强现象。更多还原

【Abstract】 The cellular metal materials can absorb a lot of energy due to their relative wide stress plateau,and it is widely used in the design of structural crashworthiness.However,some experimental results show that the stress or force enhancement will be observed when they are subjected to intense impacts,and therefore leads to severe damage of the objects being protected.The possible force/stress enhancement of ’real’ cellular material subjected to intense impact load continuous in different times is investigated by using 2D Voronoi random models.The numerical simulation results of five kinds of irregular cellular metal materials show that the force/stress enhancement occurs in the force/stress transmission of cellular materials when the intensity of the impact load reaches to a certain value.更多还原