炭黑增强橡胶复合材料的大变形细观力学模型
Micromechanics models for finite deformation of carbon black reinforced rubber composites

为考察炭黑对橡胶复合材料超弹性力学行为的影响, 首先, 利用不同填充体积分数的炭黑增强橡胶复合材料的准静态力学试验数据, 对现有的基于均质化方法的"变形放大"细观力学模型的大变形表征能力进行了评估。其次, 在此基础上提出了新的"第一不变量放大"关系, 并获得了较为合理的预测结果。最后, 利用随机序列吸附算法建立了较接近材料真实细观结构的球形颗粒填充数值模型, 进行了大变形情况下的三维数值模拟;为考察颗粒聚集效应的影响, 还设置了颗粒均匀随机分布和团聚随机分布两种形式。计算结果与试验数据的对照表明:提出的三维细观数值模型已经能在一定程度上预测填充橡胶的大变形宏观力学行为, 且颗粒团聚随机分布模型的预测能力更好一些。试验结果验证了该模型的合理性, 所建模型为进一步的相关研究提供了参考。 In order to investigate the effects of carbon black on the hyper-elastic mechanical behaviors of rubber composites, first, by employing the quasi-static mechanical test data of carbon black reinforced rubber composites with different filling volume fractions, the finite deformation characterizing abilities of existing "deformation amplification" micromechanics models which based on homogenization method were evaluated. Then, a new "1st invariant amplification" relationship was proposed on the basis, and rational prediction results were obtained. Finally, by using the random sequential absorption algorithm, the spherical particulate filling numerical models which were approximate to the real microstructures of materials were established, and 3D numerical simulations under finite deformation situation were conducted. In order to investigate the influences of particle clustering effect, two forms which were particles regular random dispersion and agglomerate random dispersion were designed. The comparison between computational results and test data indicates that the proposed 3D micromechanics numerical modes are able to predict the finite deformation macroscopic mechanical behavior of filled rubbers to some extent, and the prediction abilities of particles agglomerate random dispersion models are better. The test results confirm the reliability of proposed models, and the proposed models provide some references to the further related research. 中央高校基本科研业务费专项资金(2013-IV-109);教育部博士点基金(20130143120005)