Study On The Preparation And Mechanical Properties Of PETG/ABS Materials Based On IM And FDM

With the improvement of technology,the update speed of plastic products has become faster,and traditional Injection Molding(IM)can no longer meet people’s needs for diversified and personalized products,so Fused Deposition Molding(FDM)technology has emerged at the historic moment.In actual production,if you want to customize some plastic products and modify the mould,the production cost is high and the design cycle is long.Mould design is also difficult for products with particularly complex shapes.The use of FDM technology can produce complex parts to achieve individualization.In contrast,the product style of injection molding is relatively simple but the mechanical properties are good.In this paper,the composite samples of "PETG printing + ABS printing" and "PETG printing + ABS injection molding" were prepared based on IM and FDM.The main research results are as follows:(1)Based on the combination of IM and FDM to prepare samples,single-factor experiments and SEM observations were carried out.The tensile performance is better when the printing speed is 50mm/s.If the speed is too fast,it is easy to produce defects such as wire drawing,resulting in weakened adhesion,slower speed,the larger temperature difference between layers,and increased internal residual stress and deformation.The strength increases with the increase of the layer thickness.When the layer thickness is0.1mm,the nozzle wire is not smooth and the tensile strength becomes worse.The elastic modulus gradually decreases as the layer thickness increases from 0.1 mm to 0.25 mm,indicating that the stiffness is weakened.The tensile strength is the best when the printing angle is 45°/-45°.The reason is that the shearing force is the largest when the direction of the printing filament is 45° to the stretching direction,and the direction of the shearing force is the same as the direction of the printing filament.The filling rate is approximately proportional to the tensile strength.(2)Based on the combination of IM and FDM to prepare samples,a four-factor four-level orthogonal test was designed using the parameters in the single-factor experiment.For the tensile strength of the PETG/ABS composite sample,through reasonable parameter settings,there will be: IM +FDM>IM>FDM.According to the range analysis,the optimal combination of strength is: the layer thickness is 0.20 mm,the filling rate is 100%,the printing angle is 60°/-60°,the printing speed is 50 mm/s,and the tensile elastic modulus is the best.The combination is: the layer thickness is 0.20 mm,the filling rate is 50%,the printing angle is 30°/-30°,the printing speed is 70mm/s,and the mechanical properties are improved.A multiple regression equation on tensile strength was constructed to verify the reliability.According to SEM analysis,PETG is ductile fracture,and ABS is brittle fracture.(3)Based on the FDM "pure printing" PETG/ABS composite sample with molding time,tensile strength and elastic modulus as optimization indicators,a three-factor four-level orthogonal test was designed,and the maximum tensile strength was obtained through range and variance analysis.The best combination is that the printing speed is30mm/s,the layer thickness is 0.10 mm,and the filling rate is 100%.The optimal combination of elastic modulus is a printing speed of 25mm/s,a layer thickness of 0.10 mm,and a filling rate of 100%.Through the analysis of the comprehensive balance method,it is finally determined that the optimal combination of process parameters for composite printing is a printing speed of 30mm/s,a layered thickness of 0.1mm,and a filling rate of75%.At this time,the tensile strength is 44.73 MPa,and the elastic modulus is 758.12 MPa,and the molding time is 113 min.By optimizing the parameters,the mechanical properties are significantly improved.