碳纤维/双马树脂复合材料整体成型过程分层扩展行为实验研究

针对复合材料构件热压罐成型过程中常见的分层缺陷，考察了整体成型工艺温度对分层扩展、QY8911双马树脂基体韧性及T300/QY8911层合板Ⅰ型层间断裂韧性的影响，并通过分层扩展断面形貌深入分析了复合材料整体成型工艺中分层扩展的路径和断面破坏模式，给出了复合材料整体成型工艺和结构设计的优化建议措施。结果表明，随着整体成型最高温度的升高，分层扩展程度增大，QY8911双马树脂基体的拉伸强度和拉伸模量逐渐降低，T300/QY8911层合板Ⅰ型层间断裂韧性逐渐增大；对分层扩展断面进行SEM扫描电镜分析发现分层扩展沿着层间开裂，断面内存在基体断裂和基体/纤维界面脱粘两种破坏模式，Ⅰ型层间断裂是复合材料整体成型工艺中分层扩展的典型微观特征。

Experimental study on behavior of delamination propagation of carbon fiber/bismaleimide composites during integral forming process

To overcome the problem of frequent delamination in the autoclave process of composite components, the influence of temperature in integral forming process on delamination propagation, toughness of QY8911 bismaleimide matrix and toughness of mode Ⅰ interlaminar fracture toughness of T300/QY8911 laminates were investigated. The path of delamination propagation and the failure mode of fracture surface in the integral forming process of composites were analyzed according to the morphology of delamination propagation section. The optimization measures for integral forming process and structural design of composites were also given. The results show that with the increase of the highest temperature of the integral forming process, delamination propagation increases, the tensile strength and modulus of QY8911 bismaleimide matrix decrease gradually and the G_ⅠC of T300/QY8911 laminates increase gradually. SEM analysis of the delamination propagation section shows that delamination propagates along the interlaminar crack of laminates, and there are two failure modes in the delamination propagation section: matrix fracture and matrix/fiber interface debonding. Mode Ⅰ interlaminar fracture is a typical microscopic characteristic of delamination propagation in the integral forming process of composites.