橡胶材料的动态压缩性能及其应变率相关的本构模型

Dynamic Compression Properties and Constitutive Model with Strain Rate Effect of Rubber Material

利用Instron万能试验机与LC4超硬铝合金分离式Hopkinson压杆设备,对3种不同波阻抗的橡胶材料———炭黑母胶(Carbon Black Rubber)、硅橡胶(Silicone Rubber)和泡沫橡胶(Foam Rubber)在较大应变率范围(0.002～15 000s-1)内进行了单轴压缩实验,研究应变率对橡胶材料力学性能的影响。实验结果表明:3种橡胶的准静态与动态应力-应变曲线具有不同的应变硬化形式,且动态加载下随着应变率的增大,硬化效应逐渐增强;在准静态及高应变率(12 000～15 000s-1)压缩下,泡沫橡胶表现出多孔类材料压缩曲线的弹性、塑性崩塌及致密化3段特征。基于Rivilin应变能模型,构建了一个应变率相关的动态本构模型,模拟结果与实验结果吻合较好,可以用于描述较大应变率范围内3种橡胶的非线性应力-应变关系。

This paper presents experimental study on the quasi-static and dynamic impact response for three kinds of rubbers：carbon black rubber,silicone rubber and foam rubber by using Instron machine and SHPB device.Experimental strain rate covers a wide range from 0.002 s^-1 to 15 000 s^-1.The strain rate effects on mechanical properties of rubber materials are discussed.The results show that the quasi-static and dynamic engineering strain-stress curves exhibite different strain hardening forms.Under dynamic loading,the significant rate sensitivities are observed i.e.with strain rate increasing the hardening effect is enhanced.With quasi-static and high strain rate（12 000-15 000 s^-1） loading,the mechanical properties of foam rubbers show typical three stages：elastic deformation,plastic deformation and collapse portion.A constitutive model with strain rate effect is presented based on Rivilin strain energy function,which shows good agreement with experimental data.