聚苯乙烯泡沫颗粒散体和整体集合的准静态压缩力学特性

对颗粒聚苯乙烯(EPS)泡沫单粒及封闭容器中的大量颗粒整体分别进行了不同加载速率下的准静态压缩实验,获得相应的压缩应力应变曲线.分析了单颗泡沫颗粒内部气体对材料压缩性能的影响,以及大量颗粒用作包装材料时由于内、外部气体被挤出所引起的密度变化对整体应力应变关系的影响.研究表明:EPS泡沫是典型的闭胞材料,单颗颗粒内部气体...

THE QUASI-STATIC COMPRESSIVE BEHAVIORS OF AN EPS FOAM PARTICLE AND AN ASSEMBLY OF MANY ENCLOSED EPS PARTICLES

In this paper, we examined experimentally the quasi-static uniaxial compressive behaviors of a single EPS foam particle and an assembly of many enclosed EPS particles at different loading rates. As a representative light-weight closed-cell foam, the mechanical behavior of EPS particle is strongly influenced by the gases enclosed in the cell. The contribution of the gas inside the foam cells is analyzed in this paper. For a single foam particle, the contribution of the internal gas on its compressive behavior can be described using a gas model proposed by Ashby et al. A constitutive relationship, considering both effects of the inter gas and the loading rate, is proposed for the compressive behavior of a single EPS particle. For an assembly of enclosed EPS particles, it is shown that both the internal gas and the inter-particle gas affect the mechanical behavior of the assembly. A constitutive relationship using the apparent density of the assembly as an internal variable is proposed for describing the mechanical behavior of the assembly.