Study On Optimization Of 3D Printer Structure And Process Parameters Based On FDM Technology

Fused deposition modeling,as one of the most widely used types of rapid prototyping techniques in the word,is undoubtedly a good method when it comes to personalizing custom production and producing some complicated parts which cannot be machined by cutting tools.However,the development of FDM technology is limited by the defects that the printing accuracy of molding equipment is low and the surface quality and mechanical properties of products are difficult to meet the needs of actual products.Based on the above research background,two kinds of FDM 3D printers,Prusa-i3 and Inspire-S250,were selected as the research objects.In the process of printing,it is found that Prusa-i3 3D printers have obvious structural vibration and unstable nozzle operation,while Inspire-S250 3D printers have many process parameters.When the parameters are not set reasonably,it is found that the products are prone to deformation,displacement and even unable to form.Therefore,the mechanical structure and process parameters of Prusa-i3 and Inspire-S250 3D printers are studied and analyzed respectively.The purpose was to improve the molding accuracy and market value of FDM 3D printer and to enhance the surface quality and mechanical properties of printed products.For the research of mechanical structure optimization design of Prusa-i3 3D printer,the 3D model of Prusa-i3 3D printer was established by using UG software at first.Secondly,vibration characteristics and natural frequency of the first six modes of Prusa-I3 printer were determined by using the finite element modal analysis method.The defects that printer frame column and X-axis assembly are prone to tilt and bending deformation under vibration excitation were analyzed.Based on the conclusion of finite element modal analysis,the structural optimization design was carried out.Finally,the feasibility of the optimized overall structure was verified by printing experiment and the test of nozzle vibration acceleration during printing.The experimental results show that the stability and anti-vibration performance of the optimized structure in the printing process are improved.The surface roughness values of the printed spur gear and hollow cylinder samples are 10.8631?m and 12.691?m respectively,which are lower than those of 19.275?m and 20.198?m the products before structural optimization.The printed samples have good molding quality,the surface finish and the laminar stripe in the vertical direction are noticeably improved.For the research of process parameters optimization of Inspire-S250 3D printer,the influence of layer thickness,molding room temperature,filling gap and scanning times on the surface roughness and tensile strength of ABS printed products were studied by using the orthogonal experimental design method.By analyzing range and ANOVA of the measured data,the influence order and significance level of each process parameter on the surface roughness and tensile strength of printed products were evaluated,and the optimal combination of process parameters was given.The experimental results show that the influence of various process parameters on the surface roughness and tensile strength of printed samples is different.The sequence of the magnitude of effect of the four factors on the surface quality is as follows:layer thickness,molding room temperature,filling gap and scanning times.The combination of optimal levels are as follows:molding room temperature 80?;layer thickness 0.17 mm;filling gap 6;and scanning times 2.The sequence of the magnitude of effect of the four factors on the tensile properties is as follows:layer thickness,filling gap,scanning times and molding room temperature.The combination of optimal levels are as follows:molding room temperature 80?;layer thickness 0.30 mm;filling gap 4;and scanning times 4.The research methods and results in this paper provide an effective solution for the problems that the mechanical structure of 3D printer is poor,and the optimal combination of process parameters is difficult to determine.It has certain theoretical guidance and engineering application value for the further development of FDM molding equipment with strong structural stability,high molding quality and convenient setting of process parameters.