中文摘要：

基于X射线计算机断层扫描技术,重构了能够反映闭孔泡沫铝真实细观结构的三维有限元模型。采用数值模拟与试验测试相结合的方法,研究了泡沫铝在准静态单轴压缩载荷作用下的力学响应及其变形机制,重点关注了平台阶段及致密化阶段的变形模式。结果表明：试件中变形带的出现是压缩过程进入平台阶段的一个标志,此时棱杆和孔壁的变形以塑性弯曲为主;平台阶段,棱杆及孔壁的变形逐渐向塑性起皱与塑性屈曲转变;伴随致密化阶段的发生,变形带内部的胞孔严重坍塌,呈‘双凹圆盘’状。闭孔泡沫铝细观结构变形模式的数值模拟与试验结果相符,验证了该模型的有效性,为进一步研究各相关物理量（相对密度、加载速率等）及变形机制对其宏观吸能性能的影响奠定了基础。

英文摘要：

A three-dimensional（3-D）finite element model of the actual structure of closed-cell aluminum foam was reconstructed based on X-ray computed tomography.The mechanical response and deformation mechanism of aluminum foam under quasi-static uniaxial compression were investigated through numerical simulations and experiments,especially the deformation mode of the foam in plateau stage and densification stage.The results show that at the beginning of plateau stage,the deformation band occurs and the dominant deformation mode of cell edges and cell walls is plastic bending.During plateau stage,the deformation mode switches to plastic wrinkling and buckling.As densification stage starts,the cells within deformation band are seriously collapsed,and are ＇biconcave disks＇.The numerical simulations are consistent with experimental measurements.Thus,the model is validated,providing a basis for further investigation on the influence of corresponding physical factors（e.g.relative density and loading speed,et al）and deformation mechanism on the energy absorption capability of closed-cell aluminum foam.