| 摘要 |
The present invention is a method for casting and densification. The method is comprised of the steps of filling a mold in a pressure vessel to a predetermined level with molten metal and then increasing the pressure in the vessel such that voids formed within the metal are substantially closed without removing the mold with the metal from the pressure vessel. Preferably, after the increasing pressure step, there is the step of cooling the molten metal to ambient temperatures. In one embodiment, the increasing pressure step includes the step of increasing pressure in the vessel at a predetermined rate through the liquidus, liquidus/solidus and solidus phases of the metal. Alternatively, the increasing pressure step can include the step of increasing pressure at a predetermined rate through the liquidus/solidus and solidus phase of the metal. Alternatively, the increasing pressure step can include the step of increasing pressure at a predetermined rate through the solidus phase of the metal. The method is not limited to a type of mold or casting medium. For instance, investment or permanent molds could be used.
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