Xie Zhaonan, Huang Xicheng, Zhang Kai, Yan Shunping, Chen Junhong, He Ren, Li Jiaxing, Zhong Weizhou
Institute of Systems Engineering, China Academy of Engineering Physics, Mianyang 621999, China.
Shock and Vibration of Engineering Materials and Structures Key Laboratory of Sichuan Province, Mianyang 621999, China.
Materials (Basel). 2025 May 12;18(10):2236. doi: 10.3390/ma18102236.
The effect of thermo-oxidative aging on the hyperelastic behavior of ethylene propylene diene monomer (EPDM) rubber was investigated by a combined experimental and theoretical modeling approach. Firstly, the uniaxial tensile test of aged and unaged EPDM rubber was carried out. The test results show that the unaged EPDM rubber had the nonlinear large deformation characteristic of a "S" shape. The stiffness of the EPDM rubber was found to increase with the aging time and aging temperature. Then, in order to quantitatively characterize the hyperelastic behavior of unaged EPDM rubber, the fitting performances of the Mooney-Rivlin, Arruda-Boyce, and Ogden models were compared based on a uniaxial tensile stress-strain curve. The results show that the Ogden model provided a more accurate representation of the hyperelastic behavior of unaged EPDM rubber. Subsequently, the Dakin dynamic equation was adopted to associate the parameters of the Ogden model with the aging time, and the Arrhenius relationship was utilized to introduce the aging temperature into the rate term of the Dakin dynamic equation, thereby establishing an improved Ogden constitutive model. This improved model expanded the Ogden model's ability to explain aging time and aging temperature. Finally, the improved model prediction results and the test results were compared, and they indicate that the proposed improved Ogden constitutive model can accurately describe the hyperelastic behavior of aged and unaged EPDM rubber.
采用实验与理论建模相结合的方法，研究了热氧老化对三元乙丙橡胶（EPDM）橡胶超弹性行为的影响。首先，对老化和未老化的EPDM橡胶进行了单轴拉伸试验。试验结果表明，未老化的EPDM橡胶具有“S”形的非线性大变形特性。发现EPDM橡胶的刚度随老化时间和老化温度的增加而增大。然后，为了定量表征未老化EPDM橡胶的超弹性行为，基于单轴拉伸应力-应变曲线比较了Mooney-Rivlin、Arruda-Boyce和Ogden模型的拟合性能。结果表明，Ogden模型能更准确地描述未老化EPDM橡胶的超弹性行为。随后，采用Dakin动力学方程将Ogden模型的参数与老化时间联系起来，并利用Arrhenius关系将老化温度引入Dakin动力学方程的速率项中，从而建立了改进的Ogden本构模型。该改进模型扩展了Ogden模型解释老化时间和老化温度的能力。最后，比较了改进模型的预测结果和试验结果，结果表明所提出的改进Ogden本构模型能够准确描述老化和未老化EPDM橡胶的超弹性行为。
