硬质聚氨酯泡沫塑料压缩力学性能

THE COMPRESSED PROPERTIES OF POLYURETHANE RIGID(PUR) FOAM

研究了三种密度不同的聚氨酯泡沫塑料的低速压缩力学性能，用ＳＥＭ分析了初始胞体结构，确定了胞体尺寸及结构特性．

The mechanical properties of several PUR foams of different densities have been investigated by low speed compressive tests. Cell structural characteristics and its size ate also determined by SEM analyses. According to stress-strain curves obtained in experiments, the following conclusions have been drawn:PUR foam plastics have viscous characteristics when deformed. This kind of viscosity increases with deformation developed. However, it has nothing to do with density. The stress increases steeply at the instant of sudden change of deformation velocity. Therefore, PUR foam plastics is strain rate sensitive even though under lower strain rate loading. PUR foams plastics of different densities have different tins of stress-strain curves. In turn, they have different deformation and failure modes. The strain-rate sensitivity for PUR foam plastics increases with its density. Temperature has a clear effect on the stress-strain relation of PUR foams plastics. This effect becomes more apparent with the increases of foam density.