Research And Verification Of Extrusion Mechanism Of Multi-Color 3D Printer

FDM 3D printing is an additive manufacturing technology that uses melt-printed silk material to shape three-dimensional models quickly.It has low molding cost,no pollution and strong expandability,and it is widely used in science,education,production and daily life.At present,most FDM 3D printers can print monochromatic or two-color models,but the 3D printers that can mix multi-color are mostly for commercial production,so it is short of multi-color FDM 3D printers with characteristics of low-cost,high color mixing degree,and full-color printing.Facing the problems of multi-color FDM 3D printers,such as low color mixing degree and limited color range,a 3D printer nozzle that can achieve full color mixing is designed in this paper,and the main tasks are listed below.(1)Investigate the development status of multi-color 3D printing technology at home and abroad.On the basis of full analysis of FDM 3D printing principles,choose the near-end wire feeding plan,and formulate a color mixing scheme that combine subtractive color mixing theory and nozzle structure with multiple inlet and single outlet.Then select the ABS polymer as the printing material,and analyze its rheological behavior to prepare for the fluid simulation of the multi-color nozzle.(2)Propose a multi-inlet and single-out nozzle structure,and draw a 3D modeling of MK8 extruder based on the nozzle of the Prusa i3 FDM 3D printer.Later do some simulation experiments to determine the structural parameters of throat,heating block and nozzle.Then,based on the result of fluid analysis,adjust the inner flow angel of the nozzle,and get the geometric parameters of the multi-color nozzle.(3)Define the optimal structural parameters of the melt mixing cavity by fluid simulation.Then adjust the feed rate of the printing materials to simulate the mixing conditions of melt materials.Later consider about the main parameters that affect the printing accuracy to propose methods to revise and optimize the color mixing effect.At last,program the corresponding program for the multi-color nozzle and form a plug-in,which is convenient for the actual production,the application,and the practicality of the multi-color printer.Based on the design of the nozzle's structure of multi-color FDM 3D printer,optimize the nozzle system by the structure simulation and fluid simulation,then verify the feasibility of the design in this paper,which provide a method for the realization of efficient full color FDM 3D printer.