复合材料加筋壁板帽型筋条包覆层对界面脱粘起始的影响

INTERNAL CLADDING LAYER INFLUENCE ON THE DEBONDING OF HAT⁃STRINGER STIFFENED COMPOSITE PANELS UNDER AXIAL COMPRESSION

复合材料加筋壁板结构广泛运用于现代飞机中,此类结构在工作状态下容易发生屈曲,大量试验表明飞机复合材料加筋薄壁结构破坏的主要原因是蒙皮与筋条间的脱粘。针对帽型单筋板内部包覆层对界面脱粘起始的影响进行了研究,对帽型筋条内部全包带捻子条、半包带捻子条、不包带捻子条的三种构型进行了试验和有限元分析。分析中蒙皮与内包层之间采用三维实体单元模拟界面胶层,采用Hashin准则作为复合材料失效判据。分析得到的破坏形式与极限载荷与试验吻合良好,证明了该方法的有效性,同时研究了内包层对凸缘蒙皮之间脱粘起始的影响和凸缘蒙皮间脱粘的历程。

Debonding between flange and skin is the dominate failure mode of stiffened composite panels which are widely used in modern aircraft.The influence of internal cladding layer in hat stringer on the onset of debonding is investigated experimentally and numerically.Cohesive elements are used to simulate the adhesive layer between skin and flange and Hashin’s failure criterion is adopted to determine damage initiation of composite layers in the numerical simulations.The process of damage initiation,propagation and failure of the stiffened composite panels was simulated in detail.A good agreement between tests and numerical prediction was observed.