复合材料层板脱层开裂的复合型断裂准则

1.问题的提出 层板脱层是复合材料主要破坏模式之一;Wang等人认为基本上是断裂问题。一般均假定复合材料层板脱层开裂是基体控制的,在复合型开裂作用下的能量释放率G为各个单一型开裂作用下的能量释放率G_Ⅰ、G_Ⅱ和G_Ⅲ的代数和 G=G_Ⅰ+G_Ⅱ+G_Ⅲ (1)从下列的研究结果可看出上式有一定的不合理性。

MIXED-MODE FRACTURE CRITERION OF THE DELAMINATION ONSET FOR COMPOSITE LAMINATES

The delamination problem of composite laminates is investigated. This problem is one of the most important problems affecting the use of structure composite laminates. Here, the delamination damage in composite laminates is regarded as the line-crack and the fracture mechanics method is used. Due to the existence of the interlaminar stresses in the free-edge in composite laminates, the delamination crack is generally mixed-mode. Thus, the mixed-mode fracture criterion of the delamination onset for composite laminates is presented in this paper. Using this criterion, it is expected that the failures of various composite laminates whose major failure model is delamina ted can be analysed.