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In this paper, the main jet deposition zone control spray deposition process to solve the conventional spray deposition area and not directly with the continuous extrusion technology to match the problem. Although spray deposition technology is relatively mature, but the spray deposition area control research at home and abroad there is no relevant reports, therefore, the direction of this study has a certain novelty, innovation. The research was first to design a small spray deposition apparatus, including a nozzle, the draft tube, melting means, receiving means, cooling means, the high pressure gas device, the protection device. Has this device based on the simulation of water spray deposition, spray deposition experiments of metallic lead, 5052 aluminum spray deposition experiment. The water spray deposition simulation results show that the ejection region of the linear nozzle in a free state, a more narrow and more nearly rectangular, and determining the linear nozzle more than the ring grooved nozzle suitable for use with a continuous extrusion machine extrusion wheel groove match. In the spray deposition of metallic lead during the experiment, it has a chamfer of 60 ° and 120 ° the draft tube metallic lead spray deposition experiment, the results show that, in the the same atomizing gas under pressure, with the deflector tube extending the length of the change, chamfer 120 ° diversion tube end portion is easier to form the negative pressure effect, is more conducive to the flow of liquid metal, and the change of the negative pressure value is relatively small, the spray deposition process is more stable, so OK 120 ° chamfer draft tube as the preferred device. Linear nozzle, and the chamfer is 120 ° with the use of the draft tube, respectively, with the use of controlled spray deposition area with a baffle air knife lead spray deposition experiment, the baffle spacing is 16 to 20 mm, gas Daoqi, seam The spacing of 20 to 60mm, and the gas pressure of the gas knife 1Mpa, air knife inclination angle of 1 ° to 3 °. The results showed that the baffle in the experimental process the metallic lead blocked, this is due to the effect of the stream of metallic lead in the high-pressure atomizing air conditioning, the temperature is reduced rapidly, and injected into the solid fraction in the cold metal bezel increases rapidly easily adhered to both sides of the metal shield, as the injection proceeds, the metallic lead rapidly accumulate, causing the baffle to obstruction; under the action of the air curtain formed by the air knife, the deposition area of ??the metallic lead control Great improvement, 70 to 80% can be controlled within a range of ± 35mm, the theoretical analysis, if large enough, the pressure of the gas knife can be 100% of the metal lead control within ± 35mm, or even a small area. 5052 aluminum spray deposition experiments, improved the design of the draft tube, air knife in the atomization gas pressure of 0.4 ~ 08MPa spray deposition experiments. The results showed that the atomizing gas is 0.6MPa, the 80.7% of the 5052 deposition can be controlled within a range of ± 30mm, and the density of the deposited billets preferably. In short, under the action of the gas knife of the auxiliary device, and constantly optimize nozzle, the draft tube, and continuously adjust the atomizing gas pressure in the spray deposition process, the draft tube projecting length, the case of the gas pressure of the gas knife and other related process parameters achieved a certain, spray deposition regional control, the liquid metal is able to make 80% of control within approximately ± 30mm, but there is a gap away from the ultimate purpose, it is currently under final settlement of related experiments in order to control the deposition area .
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