The main objective of this paper is to investigate the mechanical performance of the continuous carbon fiber reinforced PLA composites (CFRPCs) printed in vacuum. A novel 3D printer which is used to manufacture CFRPCs in vacuum and a continuous carbon fiber prepreg filament production equipment which is used to produce the raw materials needed for 3D printing are first proposed. Compared with the printing in atmospheric environment, the impregnation effect of the part printed in vacuum can be effectively improved, the porosity is reduced from 13.93% to 4.18%, and the flexural strength and modulus are increased by 24.51% and 8.35%, respectively. The influences of 3D printing process parameters on the mechanical properties of the specimens printed in vacuum are systematically researched. The flexural properties of the specimens are positively correlated with the printing temperature and inversely related to the printing speed and layer thickness. When the printing temperature increases from 180 °C to 230 °C, the flexural strength and flexural modulus of the printed parts are increased by 45.73% and 31.75%, respectively. The feasibility of 3D printing continuous carbon fiber reinforced thermoplastic (CFRTP) in vacuum is demonstrated.

本文的主要目的是研究在真空中打印的连续碳纤维增强 PLA 复合材料 (CFRPC) 的机械性能。首次提出了一种用于在真空中制造 CFRPC 的新型 3D 打印机和一种用于生产 3D 打印所需原材料的连续碳纤维预浸料长丝生产设备。与大气环境打印相比，真空打印部件的浸渍效果得到有效提高，孔隙率由13.93%降低到4.18%，弯曲强度和模量分别提高24.51%和8.35%。系统研究了3D打印工艺参数对真空打印试样力学性能的影响。试样的弯曲性能与印刷温度呈正相关，与印刷速度和层厚呈负相关。当打印温度从180℃升高到230℃时，打印件的弯曲强度和弯曲模量分别提高了45.73%和31.75%。证明了在真空中 3D 打印连续碳纤维增强热塑性塑料 (CFRTP) 的可行性。