Modern Aluminum Castings

Investment Casting

Investment casting, also known as precision casting, produces precise and reliable parts that exactly match design tolerances. The process of investment casting is built on the concept of a wax pattern that is enveloped in a ceramic slurry.

What is Investment Casting?

Investment casting begins with the creation of a wax pattern in a metal die. The two halves of the die, that contain the shape of the final part, are sealed together, and injected with wax that fills the die to create the investment castings.

The wax pattern is removed from the die and placed on an assembly pattern that includes a wax sprue and gate. Multiple wax patterns of the same or diverse shapes are placed on the wax sprue. The assembly pattern, or tree, is dipped in a ceramic slurry to coat the wax patterns.

The ceramic coated tree is dipped several times in stucco to thoroughly coat it. The stucco coating is allowed to harden and form a firm covering over the ceramic coated wax patterns.

The hardened stucco coated assembly tree is heated, which melts the wax, which runs out the bottom of the assembly tree. The empty mold is subjected to 870° C or 1598° F to 1095° C or 2003° F, a process called burnout, to remove remaining moisture or wax residue as well as sinter and solidify the mold.