Evaporative-pattern casting is a type of casting process that uses a pattern made from a material that will evaporate when the molten metal is poured into the molding cavity. The most common evaporative-pattern material used is polystyrene foam.[1]
The two major evaporative-pattern casting processes are:[1]
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,[2] evaporative foam casting, foam vaporization casting, lost pattern casting, the castral process, and expanded polystyrene molding.[3][4] Proprietary terms included Styro-cast,[5] Foam Cast,[6] Replicast,[7] Policast.[4] and Lost Foam Sintered Shell (LFSS)[8]