闭孔泡沫材料3-D几何建模及力学性能分析

3-D geometry modeling and mechanical properties analysis of closed-cell foams

为建立闭孔泡沫金属材料泡孔及其孔壁结构形状数字化模型,提出在Voronoi多面体内填充空心椭球(Hollow Ellipsoid Filled in Voronoi Cell,HEFIVC),并以椭球半轴长度及其方位角为变量、胞体质量最小为目标建立优化模型,迭代模拟闭孔泡沫金属材料中气泡的长大过程,成功构建了不同孔隙率的泡沫铝几何模型。通过拟合确定了HEFIVC模型中最小孔壁厚度与孔隙率间的关系。将具有周期性边界的闭孔泡沫材料HEFIVC几何模型导入MSC.MARC有限元软件,模拟分析了低孔隙率泡沫铝的静态压缩力学性能,通过与泡沫铝压缩实验结果对比,验证了该模型的准确性。

To setup the digital model of cell for closed-cell metal foam and its wall structure,by filling hollow ellipsoid in Voronoi cell（HEFIVC）,an optimization algorithm was proposed. By taking the elliptical axial length and its direction angle as designing variables,the minimum weight of the cell as objective function,the growing up process of the bubble in the closed-cell metal foam was iterative simulated,and the 3-D geometry models with different porosity were built. The relationship between porosity and the minimum cell wall thickness of the HEFIVC model was confirmed by data fitting method. By importing the HEFIVC geometry model of closed-cell metal foam with periodic boundary conditions into the MSC. MARC,the static compression mechanical behavior of aluminum foam was simulated. The accuracy of numerical simulation results were verified through the compression experiment.