The potential to provide improved performance for advanced composites through the addition of multi-walled carbon nanotubes (MWCNTs) to carbon fiber composites is of interest in several applications. To investigate performance four types of composite specimens with different off-axis angles were subjected to progressive tensile loading. The results show that MWCNTs can improve the bearing capacity of the composite and the off-axis orientation angle can enhance the toughness of the composite. During loading acoustic emission (AE) signals were collected and they were post-processed using cluster analysis based on a Fuzzy C-Means algorithm. The analysis of the AE signals shows that data can be divided into categories which correlate with three damage modes: matrix cracking, fiber debonding and fiber breakage. The AE peak frequency characteristics of each damage mode were identified. Additional characterization was provided by using micro-computed tomography (Micro-CT) during the progressive tensile loading process. The CT images visualize damage location and evolution in the composites and data exhibit good correlations with the AE data for defects predication. The combination of AE and micro-CT technology were shown to effectively characterize damage evolution of the composites, and such data can potentially serve as a reference for the structural health monitoring of these composites when used in structures.

通过在碳纤维复合材料中添加多壁碳纳米管 (MWCNT) 来提高先进复合材料性能的潜力在多种应用中引起了人们的兴趣。为了研究性能，对具有不同离轴角度的四种复合材料试样进行了渐进拉伸载荷。结果表明，MWCNTs可以提高复合材料的承载能力，离轴取向角可以增强复合材料的韧性。在加载期间收集声发射 (AE) 信号，并使用基于模糊 C 均值算法的聚类分析对它们进行后处理。AE 信号的分析表明，数据可以分为与三种损伤模式相关的类别：基体开裂、纤维脱粘和纤维断裂。确定了每种损伤模式的 AE 峰值频率特性。通过在渐进拉伸加载过程中使用微型计算机断层扫描 (Micro-CT) 提供了额外的表征。CT 图像可视化复合材料中的损伤位置和演变，数据与用于缺陷预测的 AE 数据具有良好的相关性。AE 和显微 CT 技术的结合被证明可以有效地表征复合材料的损伤演变，并且这些数据可以作为这些复合材料在结构中使用时的结构健康监测的参考。CT 图像可视化复合材料中的损伤位置和演变，数据与用于缺陷预测的 AE 数据具有良好的相关性。AE 和显微 CT 技术的结合被证明可以有效地表征复合材料的损伤演变，并且这些数据可以作为这些复合材料在结构中使用时的结构健康监测的参考。CT 图像可视化复合材料中的损伤位置和演变，数据与用于缺陷预测的 AE 数据具有良好的相关性。AE 和显微 CT 技术的结合被证明可以有效地表征复合材料的损伤演变，并且这些数据可以作为这些复合材料在结构中使用时的结构健康监测的参考。