复合材料层合壳受冲击破坏的实验研究

 为了研究复合材料层合壳在冲击荷载作用下的破坏始因、扩展机理及破坏模式,对一组20层对称正交铺设_s的航空用复合材料UIN125B石墨/环氧树脂圆柱壳段进行了低速落重实验。试件按层合壳的曲率半径R不同分为4组,每组尺寸相同的试件7件,共完成28件试件在冲击荷载作用下的试验研究。观察并分析其破坏的发生和发展过程,通过热揭层对脱层损伤及其模式进行测试和测量,了解破坏的扩展机理及最后模式。讨论曲率半径不同对破坏区域的分布及破坏尺寸大小的影响。最后将实验测得的破坏域与计算模拟的结果作以比较,可以看到实测破坏模式与分析结果吻合较好,实测破坏面积略小于计算分析结果。

Experiment Analysis of Impact Damage of Laminated Composite Shells

For the UIN 125B graphite/epoxy composite material with symmetric cross-ply sequences of 0_4/90_4/0_2_s, which is often available in airplane, the impact-induced damage initiation, propagation and damage pattern are investigated by using a drop-weight impact test. The 20-ply laminated composite cylindrical shell panels are constructed. Specimens have 6 groups with different radii of curvatures R. Each group has 7 specimens with the same dimensions. The low-velocity impact test is made for the total 28 specimens. After impact test the specimen is inspected in an X-ray chamber. The extent of the damage is measured by means of both X-ray and C-scan techniques. The influence of radius of curvatures on damage pattern and damage area are discussed. By comparison with the experiment results, the damage patterns of simulation results are in a good agreement and the damage areas of simulation ones are little larger than those of experiments.