ABOUT Investment Casting
Technology: Investment Casting Services are metal molding operations that produce metal forms using techniques known as lost-wax or lost-foam processes. Essentially, wax or other sacrificial material is molded in the shape of the final part. It is coated with a ceramic slurry, then melted out, producing a pourable form, or flask, that receives the molten metal. After the metal solidifies, the ceramic shell is broken away, revealing the finished parts.Capable of producing parts with zero draft anglesWax patterns can be sprued to permit multiple parts from a single moldGood application of rapid prototyping for pattern makingBetter tooling life than die casting diesNo parting line
Investment casting is a traditional jewelry making method but it has applications to a range of industrial parts including turbine blades. It can produce parts with complexities similar to that of die casting but at slower rates and is generally considered applicable where part runs are less than 10,000 pieces. Where die casting is usually limited to non-ferrous metals, investment casting readily handles steels and stainless steels.
The lost foam process is nearly identical to the lost wax process except the wax burn-out step is eliminated in lost foam; the foam remains in place during pouring and evaporates upon contact with the molten metal.
Advantages: Investment casting is able to handle exotic alloys used in harsh environments.
Investment Casting Limitations Generally more expensive than sand casting or forging, but costs can be saved through minimal post cast machingA pattern must be made for every part castPatterns, especially of foam, can be easily damaged and distorted
Applications: Investment casting can be used to make complex parts with internal geometries without the use of cores. Engine headsHigh pressure pumps/valvesTurbine blades