Research On 3D Printing Process Methods Of Ceramic-based Functionally Gradient Materials

Rapid fabrication of functionally gradient materials(FGMs)faces many challenges.And the effective formation of gradient features is a significant difficulty in the FGMs manufacturing process.As imperfect fabrication methods and processes,the development and practical application of gradient functional materials have been severely hindered.With the rapid growth of emerging 3D printing technology,the fast prototyping technology based on extrusion-based 3D printing technology provides new ideas and methods for rapidly manufacturing functional gradient materials.Extrusion-based 3D printing technology has gradually developed into a 3D printing technology that can realize the co-printing of multiple materials by its adaptability to printing with numerous materials.Therefore,it is of great significance to study the multi-material printing method and process based on extrusion-based 3D printing technology according to the gradient mixing method to manufacture functional gradient materials rapidly.This paper studies the 3D printing process method of ceramic-based available gradient materials based on direct ink writing technology.The specific research results are as follows:(1)The ceramic-based gradient functional material 3D printing system was designed and developed,and the three essential components of the 3D printing system were determined.In terms of the equipment structure of the printing system,an extrusion mechanism that is convenient for printing and testing various materials was designed;In terms of software and hardware environment,the slicing process of the gradient printing process was realized based on the open-source 3D printing firmware Marlin and the slicing software Cura,which provided the basis for the mixed extrusion of multiple printing nozzles.(2)The flow model of zirconia ceramic paste printing extrusion was established,the printing extrusion process of zirconia ceramic paste under different types of printing nozzles was studied,and its stress and flow state during the printing process were analyzed.The simulation analysis of the above process was carried out by the finite element method,and the simulation results were discussed and summarized,which provided the parameter basis for the subsequent printing experiments.(3)A photocuring-assisted forming process for functional gradient ceramics is proposed in this paper.And the printing realization method of available gradient materials is studied.The control precision of the printing motor is improved by the position-speed double closed-loop control method.The photocuring assisted printing process of ceramic paste was studied,and the influence of various printing process parameters in the 3D printing process was analyzed.(4)Through the 3D printing experiment,the process parameters of ceramic paste photocuring assisted printing were studied and analyzed.Various process parameters were analyzed,and it was determined that the molding quality was better when Motor extrusion speed v=2.4μm/s,printing nozzle diameter d=0.3 mm,printing movement speed v_m=20 mm/s,printing extrusion height h=0.5 mm and the UV light power p=900m W.The gradient printing effect of the functional gradient material was verified by the gradient mixing printing experiment,and the influence of the residual slurry in the nozzle on the printing was eliminated by calibrating the printing offset.