Development Of Equipment And Process Of High Temperature Metal 3D Printing Based On Electromagnetic Induction Heating Technology

The high-energy rapid manufacturing technique is achieved by laser,plasma or electron as heat source for metal parts,which is an important branch on the research areas of additive manufacturing.However,this technology has some limitations of application such as high material cost,slow speed,expensive equipment and environmental sensitivity.To solve the above problem,this paper presents a 3D printing process and forming method for metal wire based on electromagnetic induction heating technology.The aim of research is to build a low cost metal component by low common metal wire as 3D printing material,instead of expensive metal powder,whilst the forming process and printing performance are assumed by theoretical analyses and experimental study.The work content and research results of this paper are as follows:?1?According to the requirements of electromagnetic induction heating and the principle of wire deposition,a low-cost 3D printing equipment for metal wire has been independently developed.The special induction coil,high temperature heating nozzle,atmosphere protection,mechanical movement and control circuit are studies to be satisfy with the requirements.The low melting tin alloy and high melting point copper alloy is successfully realized to be built through a high temperature special nozzle with ceramic/quartz non-magnetic property,whilst an ultra-high frequent induction coil is performed as heating source with laser temperature sensor and precision wire feeding mechanism.?2?The pure tin wire with lower melting point was used as experimental material to verify the feasibility of metal fused deposition process based on electromagnetic induction heating technology,and metal tin molded parts were tested for mechanical properties and microstructure.Experimental results show that the forming parts with good interlayer binding was achieved under the conditions of the induction frequency of 650KHz,the substrate temperature of 120°C,and the print speed of 20mm/s.The micro-hardness value of the molded part can reach 14.81HV_0.05,which is roughly equivalent to the hardness of the original material.Tensile test was carried out on molding parts filled with an angle of 90 degrees.It was found that the inter-layer bonding performance had a significant effect on its tensile strength,and some holes and cracks in the morphology analysis of molding parts.?3?The metal fused deposition experiment was conducted using a high melting point H65brass wire,and the mechanical properties of the molding part were discussed on the basis of the forming test of metallic tin.The results show that the copper alloy molding parts with good interlayer bonding performance can be printed under the conditions of induction frequency of650KHz,printing speed of 20mm/s,and head-to-substrate distance of 8mm;the surface hardness of the copper alloy molded parts is 75.26HV_0.1.The cross-section of the sample along the inward surface of the interlayer shows that the hardness of the sample is decreasing.The grain size of the molded part is larger,and the grain grows like a strip.