硅橡胶是一种高分子聚合物,可以承受大变形,用途广泛。利用改进的分离式霍普金森压杆(SHPB)实验技术,对硅橡胶试样进行了不同应变率下的冲击压缩实验,基于实验数据,利用应变能函数构建了考虑应变率效应的材料本构形式。同时,实验过程中发现,在高应变率加载条件下,材料在压缩变形后出现了损伤线区,线区直径与加载应变率及试样尺寸之间存在一定的定量关系。
Silicone rubber is a macromolecule polymer,and can suffer a large deformation.The silicone rubber specimens are tested at a series of strain rates by modified Split Hopkinson Pressure Bar(SHPB) techniques.Based on the experimental data,a constitutive model of the silicone rubber is built up based on Ogden strain energy functions.An interesting phenomenon-localized damage cycle,so called lag circle-shows up in the tested specimen under high strain-rates loading.The diameters of the damage cycle are associated with strain-rate and specimen's size.A formulation about the relations between the diameter and the strain-rate,specimen's size is presented.