Evaporative pattern casting
Evaporative pattern casting is a type of casting process that uses a pattern made from the material that will evaporate when the molten metal is poured into the molding cavity. The most common evaporative-pattern material used is polystyrene foam.
The two major evaporative-pattern casting processes are:
*Full-mold casting, also called as cavityless casting.
The main difference is that lost-foam casting uses an unbonded sand and full-mold casting uses a bonded sand (or green sand). Because this difference is quite small there is much overlap in the terminology. Non-proprietary terms that have been used to describe these processes include: cavityless casting, evaporative foam casting, foam vaporization casting, lost pattern casting, the castral process, and expanded polystyrene molding. Proprietary terms included Styro-cast, Foam Cast, Replicast and Policast.