InInvestment casting process, which also is known as the lost-wax process, is a very old technique to cast objects of art. Its roots go back to ancient China.Today, investment casting is recognised and used world wide as a technique for producing "Near Net-shape" parts at very competitive costs. Sovic Group is the leading supplier of precision investment casting in China and is one of the most experienced companies offering this specialised process. There are many reasons to choose investment casting over other processes.

The main reasons are:
>>Design freedom.
>>High surface finish.
>>Close tolerances.
>>Reduced labour, tooling and machining costs.
>>Wide variety of alloys

The term "investment" refers to the ceramic materials that are used to build a hollow shell into which molten metal is poured to form the castings. The origin of the term investment comes from the solid mold process where a plaster type material is poured or "invested" into a container that holds a clustered tree of small plastic patterns that are identical to the casting being produced. After the investment material has set, the disposable patterns are burned out leaving a hollow cavity into which the metal is poured.

The same holds true for the investment or "lost wax" casting process. Wax is injected into an aluminum die to produce a pattern that is an exact replica of the part to be produced. For every casting, a wax pattern must be manufactured. The patterns are then clustered around a central sprue and repeatedly dipped into an agitated vat of ceramic and allowed to dry. After a shell thickness of approximately 3/8" has been built; the molds are dewaxed by either flash firing at high heat (1400 °F) or autoclaving (pressure and steam). The hollow shells are then preheated to 800-2000 °F depending on the alloy to be poured and the molten metal is cast into the hot shell. After cooling, the ceramic is vibrated and blasted off the metal parts and discarded. The balance of the cleaning operations (cut off, grind, heat treat, straightening, blast) are straight forward and quite similar to the other casting processes.

Cost Savings
Because investment casting can produce parts which achieve or closely approximate finished dimensions, you can enjoy significant savings through elimination of machining operations, increased tool life and reduction of labor cost and parts scrap rate. Investment castings can provide one casting, which might have previously required several pieces made in different processes and several different materials.

Quality
If consistency has ever been a problem with other processes, investment casting is consistent from run to run within casting tolerance. Don’t worry about tooling wear, changes in dimensions, or other problems associated with alternate processes. With investment casting tooling you get the same dimensions next month, next year and up to ten years from now.