Did you know that investment casting technique dates back over 5,000 years ago? This makes it one of the oldest ways to form metal. Furthermore, this is used in a wide variety of items including dental fixtures, jewelry, airplanes, cars, and other parts of complex geometry. However, if you’re curious to find out how to create a mold for investment casting, take a closer look at the entire process.
Investment Casting 101: The Process
In order to begin the process, hot molten wax is injected into an aluminum die to create wax patterns. Doing so will set the pattern to the size and shape of the required component. The wax pattern is then assembled onto a wax feeder system with each wax assembly resembling a ‘tree-like’ structure.
Next is the investment stage where a large robot dips the wax assembly into a bath of high-grade ceramic slurry. To build up a thicker coating, larger ceramic particles are dropped onto the surface of the wax assembly while it is still wet. After everything has dried, the coating or ‘investment’ process is repeated for a number of times in order to build a 10mm-thick shell mold.
Once the final mold is dried, the ‘lost wax process’ ensues where a steam autoclave is used to melt out the wax. During this stage, the mold is fired at approximately 1,000˚C with the goal of strengthening the mold by removing all traces of any remaining wax.
While they are still hot, molten metal is poured into these molds. The heat enables the metal to run even into its thin wall sections of the hollow shell. After leaving them to cool off, the ceramic shell is broken up and the casting is cut away from the feeder system. Lastly, the castings are then submitted to careful fettling, blasting, and heat treatment.
Looking for More Information About an Investment Casting?
When it comes to investment casting, Ferralloy, Inc. is an expert with over a decade of providing the global metalworking industry with castings and other related products and services. Contact us today to learn more!