The production of advanced high quality cast components is accomplished in a Vacuum Precision Investment Casting Furnace. Using the principles of the ‘lost wax process, a ceramic mold is prepared and heated prior to casting. A measured quantity of pre-alloyed metal is then rapidly re-melted and poured into the mold under vacuum.

Most production VPIC furnaces for equiaxed casting are of the semicontinuous variety. In this case, the furnace consists of two chambers isolated by a large vacuum valve. One chamber contains the melting coil and crucible assembly and the other is used as a mold loading and unloading chamber. This maximizes the production rate of the furnace with the rate-limiting factor being the melting rate of the induction power supply.

Controlled-solidification furnaces are in general appearance similar to the semicontinuous equiax furnace, however, the upper melting chamber contains a mold-heating zone to allow heating the ceramic mold to temperatures higher than the alloy liquid’s temperature prior to pouring. The mold-heating zone can be induction or resistance heated and is often split into two or more zones to create a better thermal gradient in the mold.

The molds are placed on a water-cooled chill platen, and a baffled cooling zone is located directly below the heating zone to create a high thermal gradient for solidification in the cast component. A precision drive system controls withdrawal of the mold from the heating zone through cooling zone to create the optimum thermal gradient and, hence, grain orientation or single crystal in the cast product.