Precision Analysis,Modeling And Experimental Study Of Three Dimensional Printing Parts

Three Dimensional Printing(3DP)technology is the most vitality technology in the Rapid Prototyping.It has a lot of advantages such as simple equipment,cheap material,many kinds of material types,pollution-free in producing etc.This technology without laser system has low cost,high reliability,compact equipment,and fast molding speed which make it has a vast range of applications in the Rapid Prototyping field.But Three Dimensional Printing technology also revealed some disadvantages,for example the 3DP parts has low precision at present,especially with a larger size error and surface shape error,so Three Dimensional Printing technology has great limitations in higher precision manufacturing.In order to improve the size accuracy and surface quality of parts in 3DP,this paper used three-dimensional printer ZP310 as the experimental platform to analyze the reasons of influence the precision of 3DP parts,which obtaining the method for improving the precision of parts.This further expands the application fields of 3DP technology.This paper analyzed the influencing factors of the parts' dimensional precision in the theoretical aspect,and then the results of the theoretical analysis are verified by experiments.The X,Y,Z three directions' contraction ratio changing trend and range of parts are obtained through observing the size change of the parts which used ZP15E starch based composite powder materials.Central Composite Design(CCD)is used to design the experiment for studying the influence of printing parameters on contraction ratio,such as the layer thickness and degree of saturation level,etc.Fit the experimental data to the response surface by the two regression equation and analysis response surface for obtaining optimal process parameters combination.Through the theoretical analysis about generation mechanism of warping deformation which is the main defects affecting the dimensional accuracy,we obtained that the uneven shrinkage of the condensation layer is the fundamental cause of the warping deformation of the parts,and we verified the measures of reducing the warping deformation through the experiment.Rectangle parts which are used the gypsum powder Zp130 for materials are printed under the different printing parameters,then we used three-dimensional contour instrument to measure the surface topography of the parts,analyzing the influence of printing parameters on the surface micro-structure of parts,such as the placement,powder layer thickness and degree of saturation and so on.At last the optimal printing parameters combination and the best location for putting the parts are obtained.At the same time we calibrated the contour accuracy of 3DP parts,through compensating the leakage error of binder by the experiment.Last we compared the differences of the printing parts' contour accuracy in different areas of the forming chamber and the disparity of contour precision before and after compensation by the experiment.