新型塑料颗粒3D打印机技术方案的研究

摘要

how to use plastic particles (PLA, etc.) to complete the Fused deposition modeling (FDM) was researched, we designed a small screw extruder mechanism as the printing nozzle, combined with FDM printer which is controlled by Delta parallel structure, to achieve the purpose of rapid prototyping; simulation software STAR-CCM + was applied, numerical analysis mainly included two parts, one was on the process of plastic particles into the mechanism, the other was computational fluid dynamics analysis (CFD) on the flow of the molten plastic;DEM simulation is to solve particle feed smoothness problem, analysis the feed efficiency which is influenced by different hoppers, to ensure reasonable feed hopper is designed;regardless of the pressure fluctuations aroused by screw movement, and the heating temperature influenced the flow of melting material, the control of temperature in Heating portion influences Printing quality. By designing key parameters of extrusion mechanism, combined with experiment of test machine, a preliminary program of new plastic particles 3D printer was given.%针对如何使用工程塑料颗粒(PLA等)来完成熔融快速成型进行了研究,设计了一套小型螺杆挤出机构,与Delta并联结构的FDM打印机结合,实现快速成型的目的;应用STAR-CCM+软件进行仿真研究,数值分析主要集中在进料端塑料颗粒的DEM(离散元模型)仿真,和出料端的CFD(计算流体动力学)分析;进料端的研究目的是解决颗粒进料顺畅度问题,分析不同漏斗对进料效率影响,以确保设计合理的进料漏斗;考虑螺杆挤出的压力波动因素,及加热温度对融料的流动影响因素,出料端的温度控制影响到打印效果.通过对挤出机构关键参数的设计,结合验证机的实验;给出新型塑料颗粒3D打印机的初步方案.