论文部分内容阅读
为了准确描述复合材料编织物的各向异性力学特性,首先,基于纤维增强复合材料连续介质力学理论提出了一种考虑纤维双拉耦合的复合材料编织物各向异性超弹性本构模型,该模型中单位体积的应变能被解耦为便于参数识别的纤维拉伸变形能、双拉耦合引起的挤压变形能和纤维间角度变化产生的剪切变形能;然后,给出了模型参数的确定方法,并通过拟合单轴拉伸、双轴拉伸和镜框剪切实验数据得到了本构模型参数;最后,利用该模型对双轴拉伸和镜框剪切实验进行了数值仿真,并将模拟结果与实验结果对比分析。结果表明:提出的本构模型适用于表征复合材料编织物在成型过程中由于大变形引起的非线性各向异性力学行为。所得结论表明提出的本构模型具有简单、实用的优点,且材料参数容易确定,可为复合材料编织物成型的数值模拟和工艺优化奠定理论基础。
In order to accurately describe the anisotropic mechanical properties of composite braid, firstly, based on the theory of continuum mechanics of fiber reinforced composites, an anisotropic hyperelastic constitutive model of composite braid considering the dual-fiber coupling is proposed. The model The strain energy in unit volume can be decoupled to the fiber tensile deformation energy which facilitates the parameter identification, the extrusion deformation energy caused by the double-pull coupling and the shear deformation energy caused by the change of the angle between the fibers. Then, the determination of the model parameters Method and parameters of constitutive model were obtained by fitting experimental data of uniaxial stretching, biaxial stretching and frame shear. Finally, the numerical simulation of biaxial stretching and frame shear experiment was carried out, Comparative Analysis of Simulation Results and Experimental Results. The results show that the proposed constitutive model is suitable for characterizing the nonlinear anisotropic mechanical behavior of composite braid due to large deformation during the forming process. The results show that the proposed constitutive model has the advantages of simple and practical, and the material parameters can be easily determined, which can lay a theoretical foundation for the numerical simulation and process optimization of the composite braiding.