Investment Casting Services
CM International offers precision investment casting services for our OEM clients. We are headquartered in Chicago with manufacturing facilities located in China, which allows us to provide high-quality, cost-efficient investment casting components to our US customers. Our investment casting parts are used in many industries: aerospace, food production, medical, military, and more. It is one of the oldest processes for forming metal components, and is also known as “precision casting.”
Investment Casting Capabilities
CM International produces investment casting parts from 1”-30” in size (12mm-750mm) and works with many materials, including stainless steel, aluminum, carbon steel, iron, and zinc. We offer a 12 week lead time for large orders and our tolerances are always to customer specifications based on the size of the part, with general tolerance per ISO 2768 /ASME Y14.5-2009. One advantage to investment casting is that parts are often ready to use as is; it is the only metal forming process that can produce parts that do not require additional machining or welding.
Lost Wax Casting
Intricate shapes with thin-wall castings can be achieved with lost-wax casting. To produce a complex component, wax patterns are created to make an exact replica of the desired metal part. Assembly room temperature and humidity are closely monitored during this process to ensure the wax pattern retains dimensional stability. The wax assemblies are then processed to become a ceramic shell mold. The assemblies are dipped into a cleaning bath before being placed into a bath of slurry. If there are any bubbles, they are burst to ensure a smooth finish. Next, the assemblies are placed in a rainfall sander and every detail is covered in a sand coating. Additional coats of material are applied until desired shell thickness is achieved. Using high heat, we then remove the wax, leaving the shell available for molten metal. The metal is poured into the shells and allowed to cool. Once the metal is cooled, the shell is removed by vibrating or high pressure water jets. Using a high speed cutting wheel, the individual parts are then removed from the assembly and cleaned, finished, and tested.
Lost Foam Casting
Lost foam casting is similar to lost wax casting, except an evaporable foam is used in place of wax. The first step in this process is to machine the foam into the shape of the final metal part, meeting all of the required specifications. Then, the surface of the foam part is covered with a refractory coating. This creates a barrier between the foam and the sand. Feed and upriser components are added to the part later fill with molten metal. The foam part is then placed in a mold, filled with casting sand, and then compacted. As the molten metal is poured through the feed, the metal burns away all of the foam, leaving the same shape in metal. Once cooled, the metal casting is removed from the sand mold. The metal part is then cleaned, finished and tested to ensure it meets specifications.
Investment Casting Photo Gallery
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