Investment Casting Process

The ceramic shell molds are fired to burn out the last traces of pattern material, to develop the high temperature bond of the ceramic system to preheat the mold in preparation for casting. Because shell molds have relatively thin walls, they can be fired and be ready to pour after only a few hours in the furnace.

The hot molds may be poured utilizing static pressure of the molten metal heat, as is common in sand casting, or with assistance of vacuum, pressure and/or centrifugal force. This enables the investment casting foundry to reproduce the most intricate details and extremely thin walls of an original wax or plastic pattern.

Melting equipment employed depends on the alloy. For nonferrous alloys, gas fired or electric crucible furnaces are usually used. High-frequency induction furnaces are most commonly used for melting ferrous alloys.