Chicago Vacuum Casting
Precision Investment Castings from miniature to 50 pounds
Home About Us FAQ RFQ Contact Us 414-483-7111
Investment Casting Overview
bullet Process bullet Benefits bullet Design Examples bullet Illustration bullet History
Investment Casting Metals
bullet Aluminum bullet Aluminum Alloy bullet Brass bullet Carbon Steel bullet Cobalt bullet Bronze bullet Tool Steel
CVC Advantages
Industries Served
bullet General Tolerances bullet Linear Tolerances bullet Geometric Tolerances bullet Alloy Casts bullet Metal Casting bullet Tooling Options


quick question?Investment Casting Process

Conventional Shell Casting

Investment casting, or the "lost wax" process has been in use since the construction of the first pyramid. The Egyptians and Chinese used the process in their early history to make statues and jewelry. The investment casting method was largely ignored as an industrial process for the fabrication of parts until the demand for rapidly finished parts during World War II created the need for "near net-shape" components that could readily be put into their final form. At this time new inorganic high temperature ceramic mold binders were developed to industrialize the process applications to include high strength and corrosion resistant materials such as low to high carbon alloy steel, tool steel, stainless steel, and nickel and cobalt base alloys. Aluminum and brass alloys are available also.

It is a process capable of producing intricate shapes weighing from a small fraction of an ounce up to forty pounds or more. Some examples would be: dental appliances, jewelry, components for the automotive industry, military weaponry, jet engines, aircraft structural parts, machinery components, and many others.

In general, an injection molded wax pattern is used for each part produced which is then encased in multiple layers of ceramic material. The wax pattern is then removed from the ceramic shell mold. The mold is fired in an oven and then molten metal is poured into the cavities left by the evacuated wax pattern. Upon cooling, the resulting precision castings are cleaned and subjected to further processing such as heat treatment. At this point, many parts are in their final form and are ready for use while others may require a small amount of further processing such as machining before reaching their final form.

Because we build our ceramic molds exclusively by hand, we specialize in producing complex detail, which is not always possible for foundries that utilize robots. Our cosmetics are as good as any foundry can offer, better than most. Chicago Vacuum produces castings with an exceptionally smooth finish, typical dimension accuracy of +/- .005” and the capabilities of holding as close as +/-.003” when required. Our production lead times are among the shortest in the industry, and our quality system is based upon MIL-I-45208 with an ongoing objective of becoming ISO-9002 compliant throughout our facility. We also have the capabilities of furnishing secondary operations such as machining, non destructive testing, plating, coating, heat treat, and assembly. We also subcontract the construction of molding tools which are produced from 7075-T651 aircraft aluminum quality. We also employ a unique Solid Mold Process.