Andrzejewski Jacek, Gronikowski Marcin, Aniśko Joanna
Faculty of Mechanical Engineering, Institute of Materials Technology, Poznan University of Technology, ul. Piotrowo 3, 61-138 Poznan, Poland.
MATRIX Students Club, Poznan University of Technology, ul. Piotrowo 3, 61-138 Poznan, Poland.
Materials (Basel). 2022 Aug 5;15(15):5405. doi: 10.3390/ma15155405.
The presented research was focused on the development of a new method of sandwich structure manufacturing involving FDM-printing (fused deposition modeling) techniques and compression molding. The presented concept allows for the preparation of thermoplastic-based composites with enhanced mechanical properties. The sample preparation process consists of 3D printing the sandwich's core structure using the FDM method. For comparison purposes, we used two types of GPET (copolymer of polyethylene terephthalate)-based filaments, pure resin, and carbon fiber (CF)-reinforced filaments. The outer reinforcing layer "skins" of the sandwich structure were prepared from the compression molded prepregs made from the LCP (liquid-crystal polymer)-fiber fabric with the GPET-based matrix. The final product consisting of an FDM-printed core and LCP-based prepreg was prepared using the compression molding method. The prepared samples were subjected to detailed materials analyses, including thermal analyses (thermogravimetry-TGA, differencial scanning calorimetry-DSC, and dynamic thermal-mechanical analysis-DMTA) and mechanical tests (tensile, flexural, and impact). As indicated by the static test results, the modulus and strength of the prepared composites were slightly improved; however, the stiffness of the prepared materials was more related to the presence of the CF-reinforced filament than the presence of the composite prepreg. The main advantage of using the developed method is revealed during impact tests. Due to the presence of long LCP fibers, the prepared sandwich samples are characterized by very high impact resistance. The impact strength increased from 1.7 kJ/m for pure GPET samples to 50.4 kJ/m for sandwich composites. For GPET/CF samples, the increase is even greater. The advantages of the developed solution were illustrated during puncture tests in which none of the sandwich samples were pierced.
所展示的研究聚焦于一种涉及熔融沉积成型（FDM）技术和压缩成型的新型三明治结构制造方法的开发。所提出的概念使得制备具有增强机械性能的热塑性基复合材料成为可能。样品制备过程包括使用FDM方法3D打印三明治的芯结构。为了进行比较，我们使用了两种基于聚对苯二甲酸乙二酯共聚物（GPET）的长丝、纯树脂以及碳纤维（CF）增强长丝。三明治结构的外部增强层“表皮”由基于GPET基体的液晶聚合物（LCP）纤维织物制成的压缩模塑预浸料制备而成。由FDM打印芯和基于LCP的预浸料组成的最终产品通过压缩成型方法制备。对制备的样品进行了详细的材料分析，包括热分析（热重分析-TGA、差示扫描量热法-DSC和动态热机械分析-DMTA）以及力学测试（拉伸、弯曲和冲击）。静态测试结果表明，所制备复合材料的模量和强度略有提高；然而，所制备材料的刚度与CF增强长丝的存在比与复合预浸料的存在更相关。在冲击测试中揭示了使用所开发方法的主要优势。由于存在长LCP纤维，所制备的三明治样品具有非常高的抗冲击性。冲击强度从纯GPET样品的1.7 kJ/m增加到三明治复合材料的50.4 kJ/m。对于GPET/CF样品，增加幅度更大。在穿刺测试中展示了所开发解决方案的优势，其中没有一个三明治样品被刺穿。
