Analysis of mechanical behavior of 3D printed heterogeneous particle-polymer composites
Analysis of mechanical behavior of 3D printed heterogeneous particle-polymer composites
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DOI：
10.1016/j.compositesb.2019.05.051
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发表时间：
2019-09-15
影响因子：
13.1
通讯作者：
Pan, Yayue
中科院分区：
文献类型：
--
作者：
Joyee, Erina Baynojir;Lu, Lu;Pan, Yayue
增材制造已成为制造具有增强材料性能的非均质颗粒-聚合物复合材料的有力工具。这些合成颗粒-聚合物复合材料重量轻、坚韧，并具有显著的断裂韧性。然而，在工程颗粒微观结构取向和加载分数，以实现理想的颗粒-聚合物复合材料的应力-变形行为仍然有很大的知识差距。为了填补这一知识空白，研究断裂韧性和应力-变形模式至关重要。因此，在本文中，我们增材制造不同的颗粒链分布和颗粒加载分数的颗粒-聚合物复合材料，并研究这些复合材料的力学行为的实验和分析。此外，我们研究了层厚度对3D打印样品的杨氏模量和断裂传播路径的影响。据观察，断裂边缘保持光滑的打印与一个小的层厚度的部分，并成为不规则的不对称断裂层厚度大于一个临界值。Cox-Krenchel模型预测的杨氏模量显示出与实验结果相似的趋势，验证了模型在指导非均相颗粒-聚合物复合材料中颗粒分布、取向和浓度设计方面的可行性。然而，当颗粒链平行于力的方向排列时，预测了更高的模量，而当颗粒链垂直于力的方向排列时，预测了小得多的模量，与纯聚合物的模量一样小。对S1-0和S1-45复合材料的分析结果与实验结果吻合较好，偏差为5.5%。而S1-90的分析结果与实验结果不一致，主要是由于3D打印复合材料中颗粒链与聚合物之间的界面结合较弱。分析和实验结果均表明，颗粒体积含量高、颗粒链平行取向的颗粒-聚合物复合材料的刚度最高
Additive manufacturing has emerged as a powerful tool for fabrication of heterogeneous particle-polymer composites with enhanced material properties. These synthetic particle-polymer composites are lightweight, tough and showcase remarkable fracture toughness. Yet there is still a big knowledge gap in engineering particle microstructure orientation and loading fraction, to achieve the desired stress-deformation behavior of particle-polymer composites. To close this knowledge gap, it is essential to study the fracture toughness and stress-deformation patterns. Hence, in this paper, we additively manufactured particle-polymer composites with varied particle chain distributions and particle loading fractions, and investigated the mechanical behaviors of those composites both experimentally and analytically. Additionally, we investigated the influence of layer thickness on the Young's modulus and breaking propagation paths of the 3D printed samples. It is observed that the breaking edges remain smooth for parts printed with a small layer thickness and becomes irregular with asymmetrical fractures as the layer thickness is bigger than a critical value. The Young's modulus predicted by Cox-Krenchel model show similar trends as in the experimental results and validates the feasibility of the models in guiding the design of particle distribution, orientation and concentration in heterogeneous particle-polymer composites. Yet a higher modulus is predicted when particle chains are aligned parallel to the force direction, while a much smaller modulus, as small as the modulus of pure polymer, is predicted when particle chains are aligned perpendicular to the force direction. The analytical results of S1-0 and S1-45 composites agree with the experimental results with a deviation of 5.5%. While the analytical results of S1-90 do not agree with the experimental results, mainly due to the weak interfacial bonding between particle chain and polymer in the 3D printed composites. Both analytical and experimental results show that the particle-polymer composites with high particle volume loading fraction and parallel particle chain orientation has the highest stiffness