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为评估航空结构中常用的T300级和T800级2种碳纤维/环氧树脂复合材料层压板的冲击后压缩许用值,对2种材料体系下具有不同厚度及铺层的层板进行了低速冲击和冲击后压缩试验;讨论了冲击能量、凹坑深度、损伤面积及冲击后剩余压缩强度等之间的关系,以及厚度、铺层、表面防护等因素对其造成的影响;重点关注了2种材料体系下各组层板的目视勉强可见冲击损伤(BVID)形成条件以及含BVID层板的剩余强度。结果表明:厚度及铺层对层板的凹坑深度-冲击能量关系影响较大,而对冲击后压缩强度-凹坑深度及冲击后压缩破坏应变-凹坑深度关系影响较小,且在相同铺层比例下,BVID对应的冲击能量随厚度近似呈线性增长。X850层板的损伤阻抗性能明显优于CCF300/5228层板的,但二者损伤容限性能相当。加铜网、涂漆等表面处理显著提高了层板的损伤阻抗,但对损伤容限性能影响不大;在损伤不超过BVID时,所有CCF300/5228试件的压缩破坏应变均大于4 000με,而X850材料体系下压缩破坏应变均在3 000με之上。
In order to evaluate the post-impact compression allowable values of two kinds of carbon fiber / epoxy composite laminates commonly used in aviation structure, T300 and T800, low-speed impact was applied to the laminates with different thickness and lay-up under the two material systems And the post-impact compression test. The relationship between impact energy, pit depth, damaged area and residual compressive strength after impact, and the influence of thickness, lay-up and surface protection on the impact energy are also discussed. Visual inspection of each group of laminates under the material system barely reveals the condition of BVID formation and the residual strength of the BVID-containing laminates. The results show that the influence of the thickness and the ply on the pitting depth and the impact energy of the ply has a great influence on the relationship between the compressive strength after pitting and the pitting depth and the compressive failure strain and pitting depth after impact. At the ply ratio, the impact energy of BVID increases linearly with the thickness. The damage resistance performance of X850 laminates is obviously better than that of CCF300 / 5228 laminates, but their damage tolerance performance is quite good. Surface treatment such as adding copper mesh and painting increased the damage resistance of the laminates remarkably, but had little effect on the damage tolerance properties. The compressive failure strains of all CCF300 / 5228 specimens were all larger than 4 000με when the BVID was not exceeded, While the compressive failure strain under X850 material system is above 3000με.