Abstract Carbon fiber reinforced polymer (CFRP) multidirectional composite laminates are vital for moisture-prone structures where directional fatigue properties can be optimized. In this work, the tension-tension(T-T) and tension-compression(T-C) fatigue properties of hygrothermal aged [±454]S and [+45,−45, 0, 90]2S laminates were compared with virgin properties. The effect of fiber orientation and hygrothermal aging on moisture diffusivity, FTIR spectra, glass transition temperature, and static strength was also investigated. The fiber orientation had a minor impact on moisture diffusivity, static strength, and fatigue strength. Aging caused degradation in T-C fatigue life was higher as compared to T-T loading due to fiber-matrix debonding and matrix properties deterioration.

中文翻译：

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湿热老化和纤维取向对CFRP多向复合层压板等幅疲劳性能的影响

摘要 碳纤维增强聚合物 (CFRP) 多向复合层压板对于可优化定向疲劳性能的易受潮结构至关重要。在这项工作中，湿热老化 [±454]S 和 [+45,-45, 0, 90]2S 层压板的拉-拉 (TT) 和拉-压 (TC) 疲劳性能与原始性能进行了比较。还研究了纤维取向和湿热老化对水分扩散率、FTIR 光谱、玻璃化转变温度和静态强度的影响。纤维取向对水分扩散率、静态强度和疲劳强度的影响很小。由于纤维-基体脱粘和基体性能恶化，与 TT 负载相比，老化导致的 TC 疲劳寿命退化更高。