工程橡胶元件弹性特征参数的确定方法

Determination of Resilient Coefficients of Engineering Rubber Material

摘要:

对橡胶材料进行大形变单轴拉伸、单轴压缩和平面拉伸试验，基于非线性弹性理论拟合得出超弹性模型参数，一方面通过数值计算完整定义材料的初始剪切模量、杨氏模量、体积压缩模量、表征压缩模量，另一方面通过仿真分析准确预测大形变范围的非线性特征以及弹性体压缩变形应力应变关系对试件尺寸和试验边界条件的依赖性.而后，基于线弹性理论进行小形变单轴拉伸和压缩试验，并计算线性模量.分析结果表明，线性理论仅适用于拉伸和剪切小形变弹性体，而对于发生大形变或以压缩为主的复杂形变弹性体而言，大形变试验结合非线性理论和仿真分析是获取有效弹性特征参数的最佳手段.

Abstract:

Determination of resilient coefficients of rubber material is essential to the design and optimization of elastomers in most engineering fields. Based on the nonlinear elasticity theory, a set of experiment including uniaxial tension, uniaxial compression and planar tension tests under large deformation was conducted and coefficients of a hyperelastic model were fitted. The testing data and corresponding simulation results can be used, on the one hand, to integrallty define the initial shear modulus, Young’s modulus, bulk modulus and apparent compressive modulus of present material, and on the other hand, to accurately predict the material nonlinearity and strong dependence of compressive modulus under different test conditions. Then a set of material mechanics experiment within small deformations was performed and the corresponding linear modulus were calculated. Finally, several conclusions about small and large material mechanics experiment as well as linear and nonlinear elastic theory were proposed through comparative analysis.