| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for inexpensively manufacturing a hollow metallic body having an adequate outer surface free from an explosion mark, by using a powder sintering process. SOLUTION: The method for manufacturing the hollow metallic body made from a sintered metal comprises the steps of: applying a solution containing a raw powder of the metal and/or metallic oxide and a binder, onto the outer surface of the central core, and heating the body to dry the solution and form a coating layer of the raw powder on the outer surface of the central core; heating the core having the coating layer of the raw powder, in atmospheric air or in an inert gas atmosphere containing no reducing gas, in a temperature range of 400°C or lower to vanish the core by thermally decomposing and volatilizing it and consequently form a hollow shell made of the remaining coating layer; previously presintering the shell obtained in the step, in the atmosphere of the reducing gas containing hydrogen and/or carbon, in a temperature range of 400 to 600°C so as to preserve the shape; and fully sintering the presintered shell in the reducing gas atmosphere in a temperature range of 700 to 1,000°C. COPYRIGHT: (C)2007,JPO&INPIT
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