This paper focuses on the experimental creep compaction behavior and µCT based permeability measurements of an “Out-of-life” aerospace-grade carbon/epoxy prepreg system. The creep compaction experiments were conducted using four different thicknesses (2, 4, 8 and 16 layers) of prepreg at three different temperatures (23, 60, and 90 °C). The effect of varying the number of prepreg layers on the creep compaction strain and fiber volume fraction at various temperatures was determined. An X-ray computed tomography (XCT) technique was carried out on all samples to observe the internal fabric features of the compacted prepreg. It was observed that an increase in the number of layers reduced the overall creep property of the expired prepreg system. An XCT-based model was created to measure air permeability at room temperature and the reinforcement permeability at the three different temperatures using computational fluid dynamics. Several unit cells were extracted for image analysis and segmentation for subsequent modeling of the flow through the thickness of the prepreg at elevated temperatures. The flow fields and fluid velocity contours for different numbers of layers at different temperatures were also obtained. The probability of finding connected air flow paths for air permeability decreased as the number of layers increased. It was observed that creep compaction distorted the fabric architecture at elevated temperatures, pushing the resin out and causing an increase in the through-thickness permeability.

本文重点研究“寿命终止”的航空级碳/环氧树脂预浸料系统的蠕变压实行为和基于µCT的渗透性测量。蠕变压实实验是在三种不同的温度（23、60和90°C）下使用四种不同厚度（2、4、8和16层）的预浸料进行的。确定了在不同温度下改变预浸料坯层数对蠕变压实应变和纤维体积分数的影响。对所有样品进行X射线计算机断层扫描（XCT）技术，以观察压实的预浸料的内部织物特征。观察到层数的增加降低了过期的预浸料体系的总体蠕变性能。创建了一个基于XCT的模型，以使用计算流体力学来测量室温下的空气渗透率和三种不同温度下的增强渗透率。提取了几个晶胞用于图像分析和分割，以便随后在高温下对穿过预浸料坯厚度的流动进行建模。还获得了不同温度下不同层数的流场和流速轮廓。随着层数的增加，找到连通的空气流动路径的透气性的可能性降低。观察到蠕变压实在升高的温度下扭曲了织物结构，将树脂推出并导致通透性增加。提取了几个单位细胞用于图像分析和分割，以便随后在高温下对穿过预浸料坯厚度的流动进行建模。还获得了不同温度下不同层数的流场和流速轮廓。随着层数的增加，找到连通的空气流动路径的透气性的可能性降低。观察到蠕变压实在升高的温度下扭曲了织物结构，将树脂推出并导致通透性增加。提取了几个单位细胞用于图像分析和分割，以便随后在高温下对穿过预浸料坯厚度的流动进行建模。还获得了不同温度下不同层数的流场和流速轮廓。随着层数的增加，找到连通的空气流通路径的可能性降低。观察到蠕变压实在升高的温度下扭曲了织物结构，将树脂推出并导致通透性增加。还获得了不同温度下不同层数的流场和流速轮廓。随着层数的增加，找到连通的空气流通路径的可能性降低。观察到蠕变压实在升高的温度下扭曲了织物结构，将树脂推出并导致通透性增加。还获得了不同温度下不同层数的流场和流速轮廓。随着层数的增加，找到连通的空气流通路径的可能性降低。观察到蠕变压实在升高的温度下扭曲了织物结构，将树脂推出并导致通透性增加。