| The main purpose of the thesis is to design and make one thermal spraying cabin. The electric arc spraying gun and plasma spraying gun are linked with the thermal spraying cabin simultaneously by designed flange The sample can be alternate or laminate sprayed at the same time or individually. Using this method, we can prepare composite coatings which are compact and little oxidized or some special metal coatings which have response and hard coatings. The device as a tool to exploit new composite material, supply some special coatings in space, aviation, energy and other fields.Working process: First, treating sample by remove oil, remove rust, spray sand, then erect the test to the thermal spraying cabin, adjust the distance of spraying, tighten up the hatch door. Before spraying, preheating the sample to 500-700℃. Next, the thermal spraying cabin is vacuum production.After Ar2 is injected and the content of N2 and O2 meet the standard, the spraying starts. The arc volt is 30-33V; the current is 150-200A, the pressure of inactive gas is 0.4-0.7MPa, the power of plasma spraying is 60-100KW, the main flux is 40-60L/min, the flux of delivery powder is 8-12L/min, the diameter of spraying wire is 1.6-2.0mm,the spraying distance is 80-180mm. Spraying is stopped when the coating is formed. The sample is thermal insulation between 600℃-700℃in the spraying cabin for 25-35 minutes. The test is taken out when the temperature drops to 60℃-50℃.The parameter and the process of spraying can be effectively controlled by this method. The arc spraying was operated in the cabin using the wires of Al, Ti and stainless steel. Compared with the coating sprayed in the air, the coating sprayed in the cabin has better properties with compacted coating, less oxides, higher bond strength, less porosities and less residual stress. The composite material made by the method has higher strength and property with less cost.
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