The Study Of Key Process And Optimization In High-precision 3DP Technology

Manufacturing industry is an important industry and it directly reflects the productivity level of a country.With the economic development,the demand for processing accuracy and production efficiency are getting higher and higher.3D printing technology has the advantage of saving manufacturing time,reducing costs and not being limited by model complexity.It has become one of the most popular manufacturing technology.The printed structure has many drawbacks such as poor surface,poor accuracy and low strength because it uses inkjet sprinkler head to jet a liquid media to bind the powders together layer by layer.Parts are mainly determined by the size of the forming unit and the accuracy of the machine in the forming process.Therefore forming precision mainly depends on the size of the forming unit when the machine equipment is chosen.The infiltration of binder droplet directly affects the size of the forming unit.Study of the infiltration of the liquid plays an important role in improving the accuracy of the printed parts.The purpose of this paper is to lessen the deviation of printing and to predict the nucleus size of binder droplet infiltration in 3DP technology.The processes of the binder droplet ejection and penetration processes are studied.The industrial CT that is used to scan powders and the parameters of materials are calculated.A spherical model,which is based on the data from industrial CT scanning,predicts the nucleus size.The radius of the sphere is equal to the radius of the sand.The spreading radius of binder droplet on the material is obtained by using the experimental method,and then the nucleus size is calculated.The process of droplet infiltration is simulated by using the software Comsol and the effects of contact angle,porosity and drop height on the infiltration are analyzed in the simulation.To verify the results of the simulation,the process of infiltration are recorded by the high speed digital video camera and the nucleus size is observed by electron microscope.Based on the analysis of the simulation results,the infiltration experiment is designed to determine the appropriate process parameters.Then these parameters were optimized by orthogonal experiment.A platform and standard samples are design to verify these parameters.The study is important to infiltration experiments and provides a theoretical basis for optimization of parameters in practical processing.