各向异性Kelvin开孔泡沫模型的弹性性能

Elastic Properties of Anisotropic Kelvin Model for Open-cell Foams

在弹性小变形情况下,基于构造的各向异性Kelvin模型对开孔泡沫材料的变形进行了分析。综合考虑了胞体中斜支柱的轴向、弯曲和剪切变形以及水平支柱的轴向变形的影响,利用最小势能原理得到了材料的弹性性能与各向异性比及相对密度的关系。研究结果表明,各向异性比越大,沿胞体伸长方向的相对弹性模量和泊松比越大,而在垂直于胞体伸长方向上的相应值反而越小;两个方向上的相对弹性模量均随相对密度增加而增大,泊松比的变化趋势则正好相反。本文预测结果较好地符合了实验数据的变化趋势,且与已有的G-K模型比较接近,证明了该模型的有效性。

Based on a constructed anisotropic Kelvin model, an investigation into the elastic properties of open- cell foams was conducted under conditions of small elastic deformation. The influence of inclined struts on the elastic properties under axial, bending, and shear deformations as well as the impact of axial deformation of horizontal struts were considered comprehensively. By means of the minimum potential energy principle, the relationships between the elastic properties of the material and its anisotropic ratio and relative density were acquired. The results show that when the anisotropic ratio increases, relative elastic modulus and Poisson＇s ratio increase in the elongated direction but decrease in the perpendicular direction, and when the relative density increases in both directions the relative elastic modulus increases, but the trend of Poisson＇s ratio is just the reverse. The predicted results accord well with experimental data and current G-K model, which proves the validity of the constructed anisotropic Kelvin model.