复合材料跨尺度失效准则及其损伤演化

提出了一种新的基于物理失效模式的复合材料跨尺度失效准则, 从细观层面分别对纤维和基体的失效模式进行了表征, 将纤维失效分为拉伸失效和压缩失效, 将基体失效分为膨胀失效和扭曲失效。建立了相应的失效准则及损伤演化方法。通过正方形和六边形的代表体积单元(RVE)模型, 计算了宏观应力到细观应力的机械应力放大系数和热应力放大系数。以IM7/5250-4复合材料拉伸试验作为算例对失效模型进行了验证。计算结果与试验结果吻合较好, 表明跨尺度失效准则能够准确预测复合材料层合板的破坏。

Composite multiscale failure criteria and damage evolution

A new composite multiscale failure criteria based on mechanical failure mode was proposed, failure modes of fiber and matrix were characterized at the meso level, in which the fiber failure was divided into tension failure and compression failure, as well as the matrix failure was divided into dilatation failure and distortion failure. Corresponding failure criteria and damage evolution method were established. By means of square and hexagon representative volume element (RVE) models, mechanical stress amplification factors and thermal stress amplification factors which relate macro stresses and meso stresses were calculated. IM7/5250-4 composite tensile experiments were taken as an example to verify the failure model. Simulation results fit well with experiment results, which shows that the multiscale failure criteria is able to precisely forecast the failure of composite laminates.