特种泡沫塑料的动态力学性能研究

A Study on the Dynamic Mechanical Properties of a Special Foam Plastic

通过大尺寸分离式Hopkinson压杆对特种泡沫塑料进行了高应变率冲击实验,完整地给出了该材料在高应变率下的动态应力应变曲线,并将结果和理论上的Eyring模型进行了比较,指出了这种材料在一定的应变率范围内,具有明显的应变率效应,同时从应力应变曲线的特点来看,这种材料又有良好的吸能特性.最后通过对实验数据的拟合,提出了便于工程应用的动态本构方程.

Foam plastic has excellent capability for cushioning and energy absorbing. It is important to study its dynamic mechanical behavior and to propose its constitutive relation for application design. In this paper, with split Hopkinson pressure bar apparatus, dynamic compressive stress-strain curves were obtained from the measured incident, transmitted, and reflected waves. These curves can be explained by a constitutive equation comprising a rate-dependent modulus and a strain-dependent factor. Empirical equations were derived to characterize these mechanical properties by employing a well-known Eyring rate theory. In addition, characteristics relating to energy-absorption capability as well as static mechanical behavior were also studied.