Abstract A method combining mechanical testing, infrared thermography (IRT) and synchrotron radiation computed tomography (SRCT) is proposed for the damage evolution of 3D woven carbon/epoxy composites under tension-tension (T-T) fatigue loading. To study the relationship between the damage evolution and the stiffness degradation, fatigue tests of six specimens are carried out to different stages before detection by SRCT and optical microscope. The detected results have revealed how cracks initiate, distribute and develop with increasing fatigue cycles. Particularly, the effects of fiber yarn undulation and twist caused during the manufacturing process are discussed.

中文翻译：

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基于同步辐射计算机断层扫描 (SRCT) 的 3D 编织碳/环氧树脂复合材料在张力-张力疲劳载荷下的损伤演变

摘要 提出了一种结合力学测试、红外热成像 (IRT) 和同步辐射计算机断层扫描 (SRCT) 的方法来研究 3D 编织碳/环氧树脂复合材料在拉-拉 (TT) 疲劳载荷下的损伤演变。为了研究损伤演化与刚度退化之间的关系，在SRCT和光学显微镜检测之前，对六个试件进行了不同阶段的疲劳试验。检测结果揭示了裂纹是如何随着疲劳循环的增加而产生、分布和发展的。特别讨论了纤维纱线在制造过程中产生的波动和捻度的影响。