孔隙率对碳纤维/环氧树脂复合材料层合板湿热性能的影响

针对某飞机上应用的典型铺层(±45)4/(0,90)/(±45)2]S和(±45)/(0,90)2/(±45)]S,研究了孔隙对碳纤维增强环氧树脂基复合材料层合板的吸湿行为和层间剪切强度的影响。采用不同的热压罐固化压力制备了不同孔隙率的试样。采用显微图像分析技术对孔隙率和孔隙的微观结构特征进行了详细的分析。研究结果表明:孔隙主要分布于层间,且随着孔隙率的增大,孔隙的尺寸增大;2种层合板的吸湿率和最大吸湿量随着孔隙率的增加而增加;湿热老化和未经湿热老化的层间剪切强度都随着孔隙率的增加而下降。铺层(±45)4/(0,90)/(±45)2]S未经湿热和湿热后的层间剪切强度随着孔隙率增加分别下降6%(孔隙率:0.6%~6.3%)和9%(孔隙率:0.4%~7.0%);铺层(±45)/(0,90)2/(±45)]S未经湿热和湿热后的层间剪切强度随着孔隙率增加分别下降14%(孔隙率:0.4%~6.9%)和7%(孔隙率:0.2%~8.9%)。

Effect of porosity on the hygrothermal behaviour of carbon fiber reinforced epoxy composite laminates

The effect of void content on the moisture absorption and interlaminar shear strength(ILSS)of(±45)_4/(0,90)/(±45)_2]_s and(±45)/(0,90)_2/(±45)]_s carbon fiber reinforced epoxy composite laminates used in a aircraft was studied. The carbon fiber/epoxy laminates with different void volume fractions were prepared by applying different curing pressures. The microstructure characteristics of voids were studied using optical image analysis. The results show that the voids mainly locate between the plies and grow with the increasing void content. The rate of water uptake and the maximum level of moisture absorption in the two carbon/epoxy composite laminates increase with the increasing void content. The ILSS of aged and unaged laminates decrease with the increasing void content. The ILSS of unaged and aged(±45)_4/(0,90)/(±45)_2]_s laminates with the void volume fractions 0.6%～6.3% and 0.4%～7.0% decrease 6% and 9%,respectively.The ILSS of unaged and aged(±45)/(0,90)_2/(±45)]_s laminates with the void volume fractions 0.4%～6.9%and 0.2%～8.9%decrease 14%and 7%,respectively.