Qin Dongxue, Sang Lin, Zhang Zihui, Lai Shengyuan, Zhao Yiping
Department of Radiology, The Second Affiliated Hospital of Dalian Medical University, Dalian 116027, China.
School of Automotive Engineering, Dalian University of Technology, Dalian 116024, China.
Polymers (Basel). 2022 Mar 7;14(5):1062. doi: 10.3390/polym14051062.
The aim of this study is to fabricate biodegradable PLA-based composite filaments for 3D printing to manufacture bear-loading lattice structures. First, CaCO and TCP as inorganic fillers were incorporated into a PLA matrix to fabricate a series of composite filaments. The material compositions, mechanical properties, and rheology behavior of the PLA/CaCO and PLA/TCP filaments were evaluated. Then, two lattice structures, cubic and Triply Periodic Minimal Surfaces-Diamond (TPMS-D), were geometrically designed and 3D-printed into fine samples. The axial compression results indicated that the addition of CaCO and TCP effectively enhances the compressive modulus and strength of lattice structures. In particular, the TPMS-D structure showed superior load-carrying capacity and specific energy absorption compared to those of its cubic counterparts. Furthermore, the deformation behavior of these two lattice structures was examined by image recording during compression and computed tomography (CT) scanning of samples after compression. It was observed that pore structure could be well held in TPMS-D, while that in cubic structure was destroyed due to the fracture of vertical struts. Therefore, this paper highlights promising 3D-printed biodegradable lattice structures with excellent energy-absorption capacity and high structural stability.
本研究的目的是制造用于3D打印的可生物降解的聚乳酸基复合长丝，以制造承受载荷的晶格结构。首先，将碳酸钙（CaCO）和磷酸三钙（TCP）作为无机填料加入聚乳酸基体中，制造一系列复合长丝。对聚乳酸/碳酸钙（PLA/CaCO）和聚乳酸/磷酸三钙（PLA/TCP）长丝的材料组成、力学性能和流变行为进行了评估。然后，对两种晶格结构，即立方体结构和三重周期极小曲面-菱形（TPMS-D）结构进行了几何设计，并3D打印成精细样品。轴向压缩结果表明，碳酸钙和磷酸三钙的加入有效地提高了晶格结构的压缩模量和强度。特别是，与立方体结构相比，TPMS-D结构表现出卓越的承载能力和比能量吸收。此外，通过压缩过程中的图像记录以及压缩后样品的计算机断层扫描（CT），研究了这两种晶格结构的变形行为。观察到，TPMS-D结构中的孔隙结构能够很好地保持，而立方体结构中的孔隙结构由于垂直支柱的断裂而被破坏。因此，本文重点介绍了具有优异能量吸收能力和高结构稳定性的、有前景的3D打印可生物降解晶格结构。
