【摘要】 以聚乳酸(PLA)为基体、热塑性聚氨酯弹性体(TPU)为改性剂,采用熔融共混法通过双螺杆挤出造粒,并经线材机制得直径为(1.75±0.05)mm的三维(3D)打印线材,再进行熔融沉积成型(FDM)为PLA/TPU 3D打印制品。通过摆锤式冲击试验机、扫描电子显微镜等仪器设备研究了相形态(TPU含量)和沉积方式对PLA/TPU体系冲击性能的影响。结果表明,TPU的加入使PLA冲击韧性增强,提高幅度为631.0%;熔融沉积方式对PLA/TPU共混体系缺口冲击强度有显著的影响,其中45°/45°时冲击强度较高,提高幅度为101.9%;该研究可以为设计FDM模式的3D打印工艺参数提供科学依据。更多还原

【Abstract】 The 3 D printed wire with a diameter of(1.75±0.05) mm was prepared by melt blending through twin-screw extrusion using poly(lactic acid)(PLA) as a matrix and thermoplastic polyurethane elastomer(TPU) as a modifier. Furthermore, fused deposition molding(FDM) was performed to prepare the 3 D-printed items by use of this PLA/TPU blending wire. The effects of TPU content and deposition style on the impact properties of PLA/TPU blends were investigated by using pendulum impact tester and scanning electron microscope. The results indicated that the addition of TPU greatly improved the impact toughness of PLA by 631.0 %. The fused deposition style also exhibited a significant effect on the notched impact strength of PLA/TPU blends. The blends achieved optimum impact toughness at 45 °/45 ° to present an increase by 101.9 %. This work provided a scientific evidence for the design of 3 D printing process parameters in an FDM mode.更多还原