Study On Key Technologies Of Integrated Additive And Subtractive Manufacturing Of Heat-Resistance Poly-Ether-Ether-Ketone Resin

Functional complex part can be producted by additive manufacturing technology directly.However,the surface quality of the products produced by additive manufacturing technology is poor and can not be used directly.The advantages of subtractive manufacturing are excellent surface quality,high dimensional precision and high precision of shape.It is very important to combine the two technology.In recent years,more and more researchers have been looking at the technology of integrated additive and subtractive technology which combines the advantages of both.However,the technology is not mature enough at present.There is no in-depth theoretical guidance in control software and integrated manufacturing process.Poly-Ether-Ether-Ketone(PEEK)is a heat-resistant resin with excellent properties.It has broad application prospects in aerospace,automotive electronics,medical machinery and other fields.In some respects it can replace metal and ceramics.Compared with traditional injection molding,the PEEK material can also be producted by fused deposition modeling.In this project,the key technologies of integrated additive and subtractive of manufacturing heat-resistant PEEK resin were studied.The double heating block nozzle was designed for fused deposition modeling of heat-resistant PEEK resin.The fused deposition modeling equipment was built.The temperature of the nozzle and the heating floor was accurately controlled by the closed loop temperature control system.The fused deposition modeling of PEEK material was achieved.The temperature field,viscosity field and pressure field distribution of fused deposition modeling PEEK material were studied by finite element simulation.The fluxility of PEEK were analyzed in the runners of the nozzle.The results showed that with the increase of heating temperature and with the decrease of wire feeding speed,the melting zone of PEEK material in the nozzle runners became larger,the fluxility became better,and the extrusion pressure became smaller.In this experimental study,the suitable parameters of fused deposition modeling for PEEK were obtained.The influence of printing temperature on mechanical properties and surface quality of fused deposition modeling PEEK parts was studied.The results showed that the tensile strength,the density and the surface quality of the parts will be increased with the increase of the printing temperature.When the printing temperature was less than 380?,the mechanical properties and surface quality of the parts became worse,and the mechanical and surface quality of the parts was the best when the printing temperature was 440?.The influence of printing layer thickness on mechanical properties and surface quality of fused deposition modeling PEEK parts was studied.The results showed that the tensile strength and density of the parts became smaller and the surface roughness increased with the increase of the printing layer thickness.It was found that the mechanical properties and surface quality of the parts will be significantly worse when the thickness of the printing layer was greater than 1/2 of the nozzle diameter.The influence of printing speed on mechanical properties and surface quality of fused deposition modeling PEEK parts was studied.When the nozzle of diameter 0.6mm and 0.8mm was selected,the mechanical performance and the surface quality of the parts became worse with the increase of printing speed.It was suggested that the printing speed was not higher than 23mm/s.The nozzle of diameter 0.4mm was selected and the surface quality of the parts was better when the printing speed was 20mm/s-23mm/s.When the printing speed was lower than 20mm/s or higher than 23mm/s,and the surface quality of parts was poor.The parameters of fused deposition modeling for PEEK were optimized when the nozzle of diameter 0.4mm,0.6mm and 0.8mm were selected.The difference between the optimized parameters and the simulation results was small,and the rationality of the finite element simulation was verified indirectly.The characteristics of data processing for the fused deposition modeling were studied.The data processing system of integrated additive and subtractive manufacturing based on fused deposition modeling was developed,and the feasibility of the integrated code and data processing system was verified by the NC machining software Mach3Mill.The milling performance of PEEK parts formed by fused deposition modeling was studied.The results showed that the surface roughness of PEEK parts decreased with the increase of milling speed and the decrease of feed per tooth,and the milling parameters of PEEK formed by fused deposition modeling were optimized.