Patent DE-102009037893-A1 (DE)
Title: Producing hollow body with cavity, comprises producing molded body with outer mold partially having shape of hollow cavity, where molded body is displaceable by solvent/melt in flowable state, and coating molded body with coating material
Inventor: HERTTER MANUEL
IPC: B05D1/00
Filed: 2009-08-18
Abstract: The method for producing a hollow body (5) with a cavity (4), comprises producing a molded body (1) with an outer mold partially having the shape of the hollow cavity, where the molded body is displaceable by a solvent or melts in a flowable state, coating the molded body with a coating material (2), which forms the hollow body, and removing the molded body from the hollow body by dissolving the melts. The coating of the molded body takes by powder injection molding. During coating of the molded body, several layers are provided or applied with different material composition. The method for producing a hollow body (5) with a cavity (4), comprises producing a molded body (1) with an outer mold partially having the shape of the hollow cavity, where the molded body is displaceable by a solvent or melts in a flowable state, coating the molded body with a coating material (2), which forms the hollow body, and removing the molded body from the hollow body by dissolving the melts. The coating of the molded body takes by powder injection molding. During coating of the molded body, several layers are provided or applied with different material composition. The layers comprise functional layers for adjusting the surface of the cavity and/or protective layers for protecting the initially deposited layers before further coating steps. The protective layers comprise a water-proof lacquer layer, and metallic layers made of nickel, nickel-chromium-alloys and M-chromium-aluminum-yttrium alloys, where M is nickel and/or cobalt. The functional layers comprise slip layers to produce a diffusion coating, slip layer to produce an alitization, slip layer to produce indium-chrome plating, a metallic donor layer for a diffusion coating, chromium-, aluminum-, platinum- and/or palladium-donor layer for a diffusion coating, metallic layers for producing conductivity, hard material layers, thermal barrier layers, corrosion protection layers, wear protection layers, M-chromium-aluminum-yttrium layers where M is nickel and/or cobalt, ceramic layers, and zirconium-stabilized yttrium oxide. The coating of the molded body takes place by galvanic coating, thermal spraying, arc wire spraying, high-speed flame spraying, plasma spraying, powder injection molding, metal powder injection molding, ceramic powder injection molding, cold gas spraying, kinetic cold gas spraying, application welding, laser powder application welding, slip application, coating, spray injection and/or chemical electroless metallizing processes. The method further comprises removing a binder and/or sintering and/or heat-treating the coating material of a green body produced by injecting molding. The molded body is removed from injection-molded green blank (3), brown part or white part free from binder or finished sintered hollow body. The powder made of metal, ceramic or composite material is kept in a mold during injection molding by the binder, where the mold is removed from the hollow body not from the injecting molding body during removing the molded body. The molded body is removed by water or acid. The method comprises processing the outer mold of the deposited layer or individual layers and/or adjusting the property of the material by temperature treatment. The molded body is coated from four or five sides or all sides in a rotating or surrounding manner, where two sides are arranged to an independent spatial direction. Independent claims are included for: (1) a method for repairing and/or producing a coating with a cavity on a component; and (2) an aircraft turbine component.