Ma Lianhua, Sun Heng, Dong Xu, Liu Zhenyue, Wang Biao
Research Institute of Interdisciplinary Science & School of Materials Science and Engineering, Dongguan University of Technology, Dongguan 523808, China.
School of Quality and Technical Supervision, Hebei University, Baoding 071002, China.
Polymers (Basel). 2025 Jul 15;17(14):1936. doi: 10.3390/polym17141936.
With the extensive application of 3D-printed composites across multiple industries, the investigation into their structural reliability under complex loading conditions has become a critical research focus. This study comprehensively employs acoustic emission (AE) monitoring, digital image correlation (DIC) measurement, and micro-computed tomography (Micro-CT) visualization techniques to explore the progressive damage behavior of 3D-printed sandwich-structured composites reinforced with continuous carbon fiber sheets under three-point bending. Mechanical tests show that increasing the fiber content of face sheets from 10% to 20% enhances average bending strength by 56%, while low fiber content compromises stiffness and load-bearing capacity. AE analysis categorizes damage modes into matrix cracking (<50 kHz), debonding/delamination (50-150 kHz), and fiber breakage (>150 kHz) using k-means clustering algorithms. DIC measurement reveals significant structural deformation processes during damage progression. The AE-DIC-Micro-CT combination demonstrates an initial undamaged state, followed by damage initiation and propagation in the subsequent stages. This integrated approach provides an effective method for damage assessment, guiding the design and reliability improvement of 3D-printed composites.
随着3D打印复合材料在多个行业的广泛应用，研究其在复杂载荷条件下的结构可靠性已成为关键的研究重点。本研究综合运用声发射（AE）监测、数字图像相关（DIC）测量和微观计算机断层扫描（Micro-CT）可视化技术，探究连续碳纤维片材增强的3D打印三明治结构复合材料在三点弯曲下的渐进损伤行为。力学试验表明，将面板纤维含量从10%提高到20%可使平均弯曲强度提高56%，而低纤维含量会损害刚度和承载能力。AE分析使用k均值聚类算法将损伤模式分为基体开裂（<50 kHz）、脱粘/分层（50 - 150 kHz）和纤维断裂（>150 kHz）。DIC测量揭示了损伤进展过程中的显著结构变形过程。AE - DIC - Micro - CT组合显示了初始未损伤状态，随后在后续阶段出现损伤起始和扩展。这种综合方法为损伤评估提供了一种有效方法，指导3D打印复合材料的设计和可靠性提升。
