| 摘要 |
A method and system whereby binder can be removed from a green body much more rapidly than in prior art systems without interfering with the integrity or aesthetics of the final part by providing a binder system having at least two components and preferably a mold release agent, the binder system having differing melting points. Each binder component can have parts with different melting temperature. When the temperature is raised to a point above the intermediate temperature at which the binder system flows, binder will proceed to exude to the surface of the green body wherefrom it can be removed. The binder is removed from the surface of the green body by blowing a non-saturated chemically inert atmosphere over the surface of the green body rapidly whereby the atmosphere at a region near the surface of the green body does not become saturated with the binder vapors. As an alternative, the green body can be placed on a wick with the air being blown rapidly over the surface of the green body as well as the wick itself to volatilize the binder and remove same from both the wick and the green body. As binder is removed from the green body, since only the lower melting point component binder is actually volatilized initially, the melting point of the binder system within the green body gradually increases since more of the higher melting point component binder remains behind. For this reason, the temperature within the system is continually raised to above the then system flow temperature and below the melting point of the highest melting binder component. In this way, the highest melting point binder component continues to provide rigidity to the green body and prevent collapse or shape alteration thereof.
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