Research On Parameter Optimization Of Fused Deposition 3D Printing Based On “Controlled Shape”

Melt deposition 3D printing technology has become an indispensable manufacturing technology in today’s society because of its simple process and short forming cycle.The research of melt deposition forming includes two aspects: software and hardware.It involves pre-processing and post-processing of parts manufacturing.The software affects the forming accuracy,surface quality and mechanical properties of parts by means of algorithm optimization,data processing and parameter design planning.The hardware aspects affect the performance and processing efficiency of the printing equipment by the ways of parts design and structural transmission design.In this paper,the influence of process parameters on molding surface precision and the influence of pre-and postprocessing on molding quality are studied and the relatively optimal molding process parameters are analyzed.At the same time,it also provides help for the research of additive manufacturing of different materials.In this paper,the surface accuracy of fused deposition3 D printing is studied in the following four aspects:1.In order to improve the surface accuracy of printed parts,the forming mechanism and influencing factors of melting deposition 3D printing were studied in three stages.Firstly,the fitting errors between file format conversion and parts slice stratification are analyzed.Secondly,analyze the error of printing equipment running,the precision error of material phase transition process;Finally,the influence of post-processing on the forming accuracy of the part model is analyzed.Thereby,the influence law of each stage factors on the surface accuracy is obtained.2.The printing parameters which have important influence on molding accuracy were analyzed emphatically.For the height parameter,the influence of bevel and circular arc on the forming accuracy was analyzed,and the function relationship between the machining base Angle and the surface accuracy was analyzed by matlab simulation software.The optimum matching ratio parameters of printing speed and nozzle extrusion speed were compared.The influence of temperature on molding accuracy was analyzed by the melting law of polylactic acid.3.Orthogonal test design was carried out for the main parameters affecting the surface quality(storey height,printing speed,printing temperature,bottom plate temperature and cooling standing time).Taking dimensional accuracy as the test standard,the primary and secondary order of influence on the sample surface dimensional accuracy was obtained according to the double analysis of range and variance: Printing height > printing temperature > printing speed > bottom plate temperature > cooling standing time.According to the analysis of the test results,the optimal process parameters are obtained: the height is0.10 mm,the printing speed is 40 mm/s,the printing temperature is 200 ℃,the bottom plate temperature is 60 ℃,and the cooling standing time is 30 min.4.Using the optimal technological parameters,the complex cavity part tee pipe was used as the test object to print the whole part.This paper analyzes the surface reinforcement drawing problem of the overhanging cylindrical part in the whole printing process,and optimally deals with it by combining pretreatment and post-treatment.By comparing the experimental results,it can be concluded that the surface quality of the overhanging part of the parts is greatly improved by combining the two processing methods from the measurement data and the physical parts drawings.