先驱体陶瓷材料3D打印机螺杆挤出装置的设计与优化

Design and Optimization of the Screw Extrusion Device for a Precursor Ceramic Material 3D Printer

针对陶瓷材料硬脆性带来的难以切削加工技术瓶颈,开发了一种可用于3D打印先驱体陶瓷材料的工艺--热固沉积成型工艺(thermo-setting modeling,TSM),基于此工艺,设计并优化了先驱体陶瓷材料3D打印机螺杆挤出装置.首先,确定了先驱体陶瓷材料配比并进行材料性质测试,提出热固沉积成型工艺.其次,设计了先驱体陶瓷材料螺杆挤出装置并进行初步打印实验.再次,通过ANSYS Fluent仿真分析螺杆挤出装置在打印过程中内部流场的变化情况并为优化设计提供依据.最后,对螺杆挤出装置进行优化设计,为了得到更高的打印精度,将原有的0.6 mm喷头直径缩小至0.5 mm;仿真分析发现,将螺杆转速由40 r/min提高至60 r/min,螺杆外径与机筒内壁的间隙由0.50 mm缩小至为0.25 mm,可使打印效率提高49.1%,并通过打印实验进行验证.结果表明,该螺杆挤出装置能够满足3D打印精度和效率要求并能打印出形状复杂的先驱体陶瓷零件,为陶瓷材料零件的成型加工提供了一种途径和方法.

Aiming at the bottleneck of difficult-to-cut machining technology brought about by the hard and brittle nature of ceramic materials,a process for 3 D printing precursor ceramic materials-thermo-setting modeling(TSM)was developed.Based on this process,a 3 D printer screw extruder for precursor ceramic materials was designed and optimized.First,the ratio of precursor ceramic materials was determined and the material properties were tested.According to this,a thermosetting deposition molding process was proposed.Second,the precursor ceramic material screw extrusion device was designed and the preliminary printing experiment was carried out.Third,through ANSYS Fluent simulation,the internal flow field of the screw extrusion device during the printing process was analyzed.It will provide the basis for optimized design.Finally,the screw extrusion device was optimized.To get higher printing accuracy,the original 0.6 mm nozzle diameter is reduced to 0.5 mm.Through the simulation analysis,the screw rotation speed increases from 40 r/min to 60 r/min,and the gap between the outer diameter of the screw and the inner wall of the barrel is reduced from 0.50 mm to 0.25 mm to improve the printing efficiency by 49.1%and verified by printing experiments.Results show that the screw extrusion device designed in this paper can meet the requirements of 3 D printing accuracy and efficiency and can print complex ceramic parts with complex shapes.It provides a way and method for shaping ceramic parts.