Mechanism Of Ceramics 3D Printing Based On Micro-droplet Jetting

Ceramic materials have special functions such as high temperature resistance,corrosion resistance,ablation resistance,radiation protection,which also attract more and more attention in medical repair,aerospace and other fields.However,the traditional forming method of ceramic materials is difficult to meet the diversified requirements of modern industry.The 3D printing based on micro-droplet jetting,as a technical method of additive manufacturing,has several advantages including high forming precision,high processing flexibility,short manufacturing cycle,which makes it becoming one of the research hotpots of the ceramic material forming.In this paper,the influence of the physical properties of zirconia ceramic ink on the formation of droplets and the impact process of droplets on the substrate are simulated and analyzed by the Level-Set method.Then the property parameters and printing process parameters of ceramic inks suitable for 3D printing based on micro-droplet jetting are obtained.As the results shown,the printing experiments are consistent with the numerical simulation.Firstly,to get the property parameters of ceramic ink,the piezoelectric pulse parameters and nozzle diameters that suit for the ejection,the ejection behaviors of ceramic ink with different viscosity,surface tension and density through different piezoelectric pulses and nozzle diameters are simulated by COMSOL Multiphysics software.Secondly,with the stable of ejectable ceramic ink,a further step was studied by the COMSOL Multiphysics software to simulate the dynamics process of the droplets impact on the substrate to achieve influence rules of the droplet’s physical properties,initial velocity and the the contact angle at the equilibrium state when the ink droplets impact on the substrate.Finally,according to above simulation results,the ceramic ink is prepared and the printing process parameters are set.The simulation results are verified by the experiment with the printable ceramic ink.It is concluded that the value of the proper nozzle diameter for droplet ejection printing is 5μm to 60μm,the amplitude value of piezoelectric pulse is50 V to 70 V,and the comprehensive evaluation value of the printability of the ceramic ink is1<Z<4.The research of this paper is important for the preparation of ceramic ink and the printing parameters setting of 3D printing based on micro-droplets jetting.And it provides the theoretical and experimental basis for the applications of 3D printing high-precision ceramic components.