低密度聚氨酯泡沫压缩行为实验研究

 在室温下，对一种低密度硬质聚氨酯泡沫进行了准静态压缩及应变率在1×10³～5×10³ s^-1范围内的冲击压缩实验。结果表明，所测试的聚氨酯泡沫材料在准静态实验与动态实验之间存在明显的应变率效应，但在纯动态实验中应变率效应不明显。最后，给出了以屈服应力、密度、应变等为参量的动态压缩本构关系，且能较好地与材料的动态压缩曲线吻合。

Experimental Study of the Compressible Behavior of Low-Density Polyurethane Foam

The compressive stress-strain behaviors of polyurethane foams in four different mass densities have been tested by SHPB at strain rates of 1×10³～5×10³ s^-1. Experimental results show that the compressive behavior of the polyurethane foam is sensitive to the strain rates between quasi-static experiments and SHPB experiments. However, the behavior is not sensitive to the strain-rate under condition of dynamic compression. A experiential constitutive relation, which considers density effect of the foams on materials features at high strain-rates, has been proposed based on Sherwood model. The relation is well agreed to the experimental data.