Investment Casting Often called the "lost wax process", today's technological advances allow the production of parts in high or small volume with extraordinary precision in most castable metals.
Lost Wax Process
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Special Wax is injected into metal die to make wax patterns.
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Wax patterns (replica of part) assembled into a cluster around a wax runner system.
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The “Tree” of patterns then coated with layers of a refractory material.
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Each layer being dried or chemically cured before the next layer is applied.
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Assembly is heated to remove the wax & fired at high temperature to bond the mold.
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The mold is heated and molten metal poured.
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When cool, the mold material is removed.
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Castings are removed from the runner system for secondary process and final finishing.
Lost Foam Process
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Polystyrene (or other Expandable Polymers) are injected into metal die to make EPS patterns.
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EPS patterns together form complex shapes. These pre-forms are assembled into a cluster around a sprue then coated with a refractory paint.
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The cluster is invested in dry sand in a simple molding box and the sand compacted by vibration.
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Metal is poured, vaporizing the EPS pre-form and replacing it to form the casting.
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Castings are removed from the runner system for secondary process and final finishing.
Special characteristics of Investment casting
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High production rates, particularly for small components.
