| 摘要 |
A metal is disclosed of degating clustered metal castings produced by ECP in which molten metal (27) is gravity poured into a dry, unbonded sand mold (9) for solidification, the mold containing a plurality of consumable foam patterns (17) interconnected by a complex centralized gating system (23). The method is improved by forcing purge air through the unbonded sand mold (9) just prior to the solidificatin of the core metal of the gating system (23), the purge air being forced into such mold at a predetermined pressure (such as 80-120 psi) and for a period of time (such as 10-20 seconds), causing the gating system (23) to disintegrate into pieces or beads (29) of metal. The elapsed period of time from the moment of pouring the molten metal into the mold to the moment at which the purge air is injected into the mold is critical and for certain metals is usually in the range of 3-5.7 minutes. |
