Research On Additive Manufacturing Of Automobile Parts With High Performance Special Engineering Plastics Polyphenylene Sulfide

As society attaches importance to environmental protection and sustainable development,energy conservation and emission reduction has become an important mission for the development of the automotive industry.Lightweight of automotive is one of the important ways to save resources and reduce exhaust emission.The polyphenylene sulfide(Polyphenylene sulfide,PPS)has high strength and excellent performance,and it is an ideal material for the lightweight of automobiles.However,the traditional manufacturing method is limited by its own processing technology,and it can no longer meet the current needs of society for car weight reduction and the pursuit of personalization.This research that the toughness of the prepared PPS 3D printing filaments are improved by controlling the parameters of the double screw extrusion process and adjusting the cooling conditions of the extruded filament,and the PPS filaments are made suitable for 3D printing,and PPS 3D printing system is independently developed.It avoids the filament fracture.In order to improve the packing density of PPS 3D printing samples and reduce the internal voids,the effects of the outline overlap rate and the extrusion multiplie on the tensile strength of PPS 3D printing samples were studied through single-factor experiments.The results show that the outline overlap rate and extrusion multiplie have a significant effect on the tensile properties of PPS 3D printing samples.The tensile strength and modulus of elasticity of the printing sample are higher when the outline overlap rate is 60%and the extrusion multiplie is 1.2.The internal voids of the sample are significantly reduced,and the packing density is increased.In order to obtain the optimal printing parameters for PPS 3D printing,the effects of the raster angle,the number of outline shell,and the layer thickness on the mechanical properties of the PPS 3D printing sample in terms of tension,compression,and impact were tested through single-factor experiments.The experiments results show that the tensile strength is the best when the raster angle is0~o,the number of outline shell is 3,and the layer thickness is 0.2mm.The compressive strength is better when the number of outline shell is 3 and the layer thickness is 0.4mm.The impact strength is better when the raster angle is 45°,the number of outline shell is 1 and the layer thickness is 0.2mm.In order to improve the comprehensive properties of the PPS 3D printing samples by changing the thermal environment of the 3D printing process,the warpage caused by the uneven of the crystallization during the printing process of the PPS is reduced.Through heat treatment method,the mechanical properties of PPS 3D printing samples are improved.The results show that the mechanical properties of PPS 3D printed sample under air-cooled conditions are lower than those without air cooling.However,the dimensional accuracy of the sample is significantly improved.Comparing the mechanical properties of PPS printing samples with different heat treatment temperatures,the tensile strength and compressive strength of the printing sample with the heat treatment temperature of240~oC are highest.With the increase of the heat treatment temperature,the crystallinity of the sample increases.According to the theory of polymer physics,the rigidity of the PPS 3D printing sample increases,the toughness decreases,and the impact strengt of the printing sample after heat treatment decreases significantly.Automobile parts with complex structure are successfully printed by using Self-developed PPS 3D Printing System.Based on reverse engineering,the dimensional deviation of automotive parts of PPS 3D printing is analyzed.The deviation of 89.81%of data points is in the range of-0.15~0.1mm,and it shows that automotive parts of PPS 3D printing has higher dimensional accuracy.