| 摘要 |
PROBLEM TO BE SOLVED: To faithfully replicate a minute shape and to prevent the defects such as shrinkage cavity, crack, misrun, by melting an alloy material, heating to a specified temp., pouring molten alloy material immediately into a cooled mold and rapidly cooling it. SOLUTION: The alloy material is heated to the temperature higher than the m.p. of the alloy +200 deg.C after melting. Desirably, the temp. of the cooled mold is not higher than the crystallizing temp. of the casting alloy. Since the super-cooling metal is not subjected to a phase transformation in the molten state at the solidifying time, the gas is not generated and the molten metal can be heated to high temp. In the casting of the super-cooling metal, since the molten metal is beforehand melted at the high temp., the molten metal is run over the minute shape and not solidified during casting into this mold. When the molten metal is run over the all corners, the molten metal is vitrificated by being rapidly cooled with the mold to produce the super-cooling metal. As an ornament and a dental material produced with a precision casting, the super-cooling metal of Pd-Cu-Ni-P or Zr-Al-Ni-Cu-Pd is used.
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