成型工艺对复合材料加筋结构脱粘性能的影响

Effects of Forming Process on Composite Stringer-Stiffened Panels Debonding

采用四点弯曲试验及有限元模型对比分析两种成型工艺下,工字型加筋结构试验件的破坏过程及破坏机理。研究表明:共固化试验件比二次胶接试验件损伤门槛高,且损伤扩展缓慢,表现出较好的承载能力;共固化试验件损伤主要发生在筋条蒙皮连接界面,且填充区也发生破坏;二次胶接试验件损伤主要发生在胶膜内部。在试验的基础上建立渐进损伤有限元模型,考虑两种成型工艺的不同及工字型筋条铺层角的不对称,有效地模拟两种工艺下的破坏。

In order to research the effects of co-curing and secondary bonding on composite stringer-stiffened panels, the paper contras- ted the difference between them in damage process and failure mechanism of I-shaped stringer-stiffened panels were contrasted. By con- ducting four-point bending tests and building finite element models, the load and location at the initial damage propagation of the struc- ture were obtained. The results demonstrate that co-curing specimens have higher damage threshold and slower damage propagation, which bring better loading capacity. For co-curing specimens, failures happen at the interface of the skin and stiffener, and the core re- gions of the stringer also fail. However, secondary bonding specimens typically fail inside the glue. Considering about the difference of the two forming processes and asymmetry of the I-shaped stringer, the finite element model was established to simulate the damage ef- fectively.