Mechanical behavior of liquid nitrile rubber-modified epoxy resin: Experiments, constitutive model and application

摘要

Quasi-static and dynamic experiments were carried out to examine the influence of liquid nitrile rubber (LNBR) on the compressive behavior of epoxy resin. The quasi-static tests were performed on an electronic universal machine under strain rates of 10(-4)/s and 10(-3)/s, while a Split Hopkinson Pressure Bar (SHPB) system was adopted to conduct the dynamic tests for strain rates up to 5600/s. The standard Zhu-Wang-Tang (ZWT) nonlinear viscoelastic model was selected to predict the elastic behavior of LNBR/epoxy composites under a wide range of strain rates in this study. After several necessary derivations and data fittings, a set of ZWT model parameters for the tested materials were finally achieved. Meanwhile, the dynamic response of a typical high-overload measurement system encapsulated by LNBR/epoxy composites under impact loading was simulated by LS-DYNA, where the ZWT model was used to simulate the mechanical behavior of LNBR/epoxy composites with model parameters obtained from the experiments. It was concluded that both the resistance to failure and protective effect of epoxy resin could be enhanced by 10% LNBR additive. However, 25% LNBR additive would decrease the mechanical properties of the epoxy resin.