孔隙对碳纤维/环氧复合材料层合板层间剪切疲劳性能的影响

Effect of void on the interlaminar shear fatigue of carbon fiber/epoxy composite laminates

  • 摘要: 研究了孔隙对碳纤维增强环氧树脂基复合材料层合板[(±45)/04/(0, 90)/02S的静态层间剪切强度和层间剪切疲劳性能的影响。采用不同的热压罐压力制备了孔隙率为0.4%~6.6%的试样。采用显微照相法和图像分析技术对孔隙率和孔隙的微观形貌进行了分析。研究结果表明, 随着热压罐压力的降低, 大孔隙(S>7.85×10-3mm2)所占的比例逐渐增加, 平均孔隙率增加。在孔隙率为0.4%~6.6%时, 每增加1%, 复合材料层压板的层间剪切强度下降2.4%。随着孔隙率的增加, 层压板的疲劳寿命降低。与静态试验相比, 孔隙率对层压板疲劳性能的影响比对静态性能的影响大。大孔隙的存在促进了疲劳裂纹的产生和扩展。

     

    Abstract: The effect of void content on the static interlaminar shear strength and interlaminar shear fatigue properties of carbon fiber reinforced epoxy [(±45)/04/(0, 90)/02Scomposite laminates was studied. The laminates with void volume fraction 0.4% ~ 6.6% were prepared by applying different autoclave pressure. The void content and microstructure characteristics of voids were studied using optical image analysis. The results show that the fraction of large voids(S>7.85×10-3mm2) and mean void content increase with the decreasing autoclave pressure. Each 1% increase in void content with the void volume fraction in the range 0.4% ~ 4.6% induces a 2.4% reduction in interlaminar shear strength. The interlaminar shear fatigue life decreases with the increasing void content. The effect of voids on fatigue is more significant than on static failure. Large voids promote the initiation and propagation of cracks.

     

/

返回文章
返回