三元乙丙材料粘超弹本构模型研究

利用等速拉伸和拉伸-回复实验研究三元乙丙（EPDM）包覆层材料的力学特性，提出采用有限变形条件下的超弹本构模型及线粘弹性本构理论相结合的方法建立一种粘超弹本构模型，在此基础上进一步研究模型参数的获取方法。研究结果表明：该材料具有典型的超弹性力学行为特征，并呈现出明显的率相关效应；所建立的粘超弹本构模型能够较好地描述该材料的单轴力学行为，在一定程度上可对使用该包覆层材料的固体火箭发动机的结构完整性分析提供理论参考。

Research on Visco-hyperelastic Constitutive Model of EPDM

The constant rate uniaxial tension tests and tension-recover tests are conducted to obtain the accurate mechanical property of the EPDM insulation material. A visco-hyperelastic constitutive model is developed based on the mechanical behavior characteristics of EPDM. The method is established by applying the hyperelastic theory which was established under finite deformation condition in combination with linear viscoelastic theory. Then the way to obtain the model parameters is proposed, which is simple and easy to be generalized. The results show that EPDM has the typical hyperelastic mechanical characteristics, and presents a rate-dependent effect. The visco-hyperelastic constitutive model proposed can describe the uniaxial mechanical property of EPDM accurately. The model can provide a theoretical reference for structural integrity analysis of solid rocket motor made of EPDM insulation material.