Abstract: A method for manufacturing a mold includes providing first information regarding a location of a shrinkage hole generated during hardening of a molten metal in a shell mold. Second information regarding a change in the location of the shrinkage hole in response to adjustment of a heat transfer rate of the shell mold is obtained. The heat transfer rate of the shell mold is adjusted to shift the shrinkage hole to a predetermined location.

Abstract: A method for manufacturing a mold includes providing first information regarding a location of a shrinkage hole generated during hardening of a molten metal in a shell mold. Second information regarding a change in the location of the shrinkage hole in response to adjustment of a heat transfer rate of the shell mold is obtained. The heat transfer rate of the shell mold is adjusted to shift the shrinkage hole to a predetermined location.

Abstract: A 3D jet printing apparatus having a reciprocating jetting molding mechanism includes: a molding platform mechanism, a jet printing mechanism, and a vertical lifting mechanism; where the molding platform mechanism has a molding area plane; the jet printing mechanism is provided above the molding platform, and can correspondingly perform reciprocating movement of forward and reverse strokes; the jet printing mechanism includes a powder spreading unit, powder supply units, and jet printing units; the powder supply units can drop a powder material to the molding area plane; the powder spreading unit then spreads flat the powder material on the molding area plane, and subsequently the jet printing units perform binder jet printing on the powder material that is spread flat; and after the jet printing mechanism performs a stroke once, the vertical lifting mechanism adds a vertical stacking distance between the jet printing mechanism and the molding platform mechanism.