摘要
该文探讨不可压缩橡胶弹性材料的本构模型.考虑到小变形时分子链的端矢分布符合高斯函数,而大变形时符合非高斯函数,提出一个混合模型,用高斯链网络模型来描述小变形而用8链网络模型来描述大变形.引入权重函数,使小变形和大变形情况下混合模型分别退化或趋于高斯链网络模型和8链网络模型.由Treloar拉伸实验数据拟合得到模型参数,通过这些材料参数混合模型对等双轴拉伸和纯剪切变形模式的预测结果与Tre-loar实验数据基本吻合,说明混合模型具有同时描述不同变形模式的能力.通过比较分析,混合模型的总体预测精度均优于高斯链网络模型和8链网络模型,特别是对剪切变形.
The constitutive model of incompressible rubber materials is investigated in this paper. Based on the fact that the orientation distribution of the end-to-end vector of a rubber chain satisfies the Gaussian function at small strains, while it behaves in a non-Gaussian manner in large stretch regime, a hy- brid hyperelastic constitutive model is prOposed by combining the Gaussian network model for small strains and 8-chain network model for large stretches. A reasonable weight function is applied to reduce the hybrid model to the Gaussian network model and 8-chain network model,respectively,at small strain and at large stretch. With the material constants obtained by fitting the uniaxial extension data from Treloar with Gaussian network model and 8-chain network model,the predictions from the hybrid model for equi-biaxial extension and pure shear are in good agreement with the test data, and shows significant improvements in modeling accuracy as compared to the two constituent models, especially for shear data.
出处
《固体力学学报》
CAS
CSCD
北大核心
2008年第3期277-281,共5页
Chinese Journal of Solid Mechanics
基金
国家自然科学基金(10772156)资助
