碳纤维复合材料短梁剪切疲劳特性

 研究了碳纤维增强双马来酰亚胺复合材料的层间剪切静态与疲劳加载性质,分析了不同基体、不同铺层界面对层剪性质的影响。给出了层剪疲劳加载的S-N曲线;讨论了层间剪切损伤和增强机理,观察了微观特征。与碳/环氧复合材料相比,双马来酰亚胺基体复合材料在碳纤维和基体之间粘接良好,从而改进了纤维抗疲劳裂纹扩展的能力。

SHORT BEAM SHEAR FATIGUE BEHAVIOUR OF CARBON FIBRE COMPOSITES

This paper concerns with static and fatigue behaviour of interlaminar shear in carbon fiber reinforced modified BMI resin matrix composites. The effects of interface with various kinds of resin matrix and different stacking sequence on interlaminar shear behaviour are analysed. The S-N life curves of interlaminar shear fatigue loading are given. The results show that the static and fatigue behaviour is enhanced by modified BMI resin matrix. And the twice-modified matrix is better than once-modified matrix in these behaviour. Typical shear stiffness reduction curve and fatigue damage development curve make it clear that the initial damage increases rapidly then increases at stable rate in the most of fatigue life, until the damage finally increases abruptly to failure. Interlaminar shear damage and strengthen mechanism associated with fractographic features are discussed. Compared with the carbon/epoxy composite, BMI resin matrix composites have good bonding strength between the carbon fibre and matrix, so that improves the ability of fiber to resist the fatigue crack propagation.