Study on High Impact-resistant Stacking Sequence of CFRP Laminated Composites

CFRP层合复合材料高抗冲击堆叠顺序研究

基本信息

批准号：
01550078
负责人：
KASANO Hideaki
金额：
$ 1.28万
依托单位：
Takushoku University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1989
资助国家：
日本
起止时间：
1989 至 1990
项目状态：
已结题

项目摘要

The goal of the present research is to show how the impact-induced damage of CFRP of CFRP (Carbon Fiber Reinforced Plastics) is reduced by appropriately selecting the stacking sequence of unidirectional carbon fiber spreーpreg sheets. An air gun type impact testing machine is designed and manufactured to generate impact damage. This testing machine makes it possible to propel the steel balls of diameters 5mm and 10mm with maximum velocities of 160m/sec and 120m/sec, respectively. The impact damage is expected to occur between two layers with different fiber directions accompanied by delaminations. So the specimens of angle-ply laminate composites with [0^ﾟ _6/0^ﾟ _<10>/0^ﾟ _6] are employed, in which 6 kinds of ply-angle such as theta^ﾟ=15, 30, 45, 60, 75 and 90 are selected. In the impact testing, 2 kinds of steel balls mentioned above are propelled with the same velocities of 60.4m/sec. The inside of the specimens flatwise impacted are observed through a scanning acoustic microscopy, and their cross-sections are observed through a scanning electron microscopy as well. Results obtained are summarized as follows : (1) characteristic damage patterns of delaminations are seen on 0^ﾟ/theta^ﾟ and theta^ﾟ/0^ﾟ interfaces where fiber orientations are changed, and the area of the latter is considerably large compared to the former, (2) the damage areas increase with an increasing diameter steel ball or plyangl, (3) many transverse cracks are observed in the cross-sections, (4) cracks corresponding to other delaminations than those mentioned above are also seen, (5) initial compression Young's moduli before and after impact are almost the same. The conclusion is that the fiber oriectations suitably selected contribute to the reduction of the impact-induced damage and the transverse crack initiation must be prevented as well. The future work is to consider this problem from a theoretical point of view.

本研究的目的是展示如何通过适当选择单向碳纤维预浸料片材的堆叠顺序来减少CFRP（碳纤维增强塑料）的冲击引起的损坏，设计并设计了气枪式冲击试验机。该试验机可以以 160m/sec 的最大速度推动直径 5mm 和 10mm 的钢球。分别为 120m/sec 的冲击损伤预计会发生在具有不同纤维方向的两层之间，并伴有分层。采用ﾟ_6]，其中θ^ﾟ=15、30、45、60、75等6种铺层角度冲击试验中，采用上述2种钢球，以60.4m/sec的相同速度推进，通过扫描声学显微镜观察平面冲击的试样内部，并观察其截面。也通过扫描电子显微镜获得的结果总结如下：（1）在 0^ﾟ/theta^ﾟ和上观察到分层的特征损伤模式。 theta^ﾟ/0^ﾟ界面，纤维取向发生变化，且后者的面积相对于前者相当大，(2)损伤面积随着钢球或plyangl直径的增加而增加，(3)许多横截面中观察到横向裂纹，（4）还可见与上述以外的其他分层相对应的裂纹，（5）冲击前后的初始压缩杨氏模量几乎相同，结论是纤维。适当选择的方向有助于减少冲击引起的损坏，并且还必须防止横向裂纹的萌生。未来的工作是从理论角度考虑这个问题。