微孔聚氨酯弹性体力学性能的有限元模拟

Finite Element Simulation on the Mechanical Properties of Microcellular Polyurethane Elastomers

利用COMSOL Multiphysics V4.4多物理场耦合分析软件,构建了微孔聚氨酯弹性体的二维计算模型.不仅计算了控制孔数不变改变孔径引起的孔密度的变化对应力的影响,而且还计算了控制孔径不变改变孔数引起的孔密度的变化对应力的影响.模拟结果发现孔密度是影响材料力学性能的重要因素,即当孔密度小于0.4时,应力随孔密度成线性增大,而当孔密度大于0.5时,应力随孔密度成非线性增大,泡孔的增韧作用显著.不仅如此,还发现减小泡孔孔径的波动范围有利于材料力学性能的稳定.

A two-dimensional microscopic model of microcellular polyurethane elastomer （MPUE） was established by using COMSOL MultiphysicsV4.4 of the multiphysics finite element analysis. Based on the same hole size, the effect of the hole density was calculated, as a result, it significantly affects the mechanical properties of the MPUE. In addition, based on the same hole number,the corresponding hole density also affects the mechanical properties of the MPUE. The results indicate that the hole density is important in affecting the mechanical properties of the MPUE. When the hole density is less than 0.4,the stress increases linearly with the increase of the hole density ; while when it is greater than 0.5, the stress increases nonlinearly with the increase of the hole density and the toughening effect of the holes are more obvious. In addition, the fluctuation of the hole size makes an increase of the stress, while reducing the variance of the hole size can improve the stability of the mechanical properties of MPUE.