EPDM非线性力学行为及其拉伸速率特性研究

In order to study the tensile rate dependence of EPDM mechanical behavior,uniaxial tensile tests of EPDM at 3 mm/min,30 mm/min,300 mm/min and 500 mm/min were carried out,respectively.The nonlinear mechanical behavior laws and tensile rate characteristics of EPDM were analyzed.Based on the fractional-order Kelvin-Vogit,ZWT and OGDEN models,the experimental curves of different tensile rates at 160% strain were fitted,and the characterization ability of the models was compared and studied.The results show that the whole loading curve of EPDM presents a typical S shape,and has significant nonlinear hysteresis characteristics.The larger the tensile rate,the larger the area of hysteresis loop,and the stronger the damping loss capacity.When the strain is greater than 68%,the tensile rate has a significant effect on the mechanical properties of EPDM,and hardening occurs.The fractional Kelvin-Vogit and OGDEN models are suitable for the characterization of mechanical behavior of viscoelastic materials of EPDM when the strain is less than 68% at a low tensile rate,while the ZWT model is suitable for the characterization of mechanical behavior of viscoelastic materials of EPDM when the strain is more than 100% at a high tensile rate.The ZWT model also has a good fitting effect at low tensile rate.The results can provide a useful reference for the performance evaluation and optimization of EPDM products.