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Lost foam Casting

Lost foam casting is a type of investment casting process that uses foam patterns as the sacrificed pattern to produce metal parts and it is used particularly for automotive applications. LFC is a “cavityness” metal casting technique since no tooling/mould is needed.

Firstly, foam patterns, made by Expandable Polystyrene (EPS) are assembled with glue and forming a cluster like as investment casting. Then, the foam cluster is covered with a thin layer of heat resistant coating by dipping, spraying or pouring. The coating forms a barrier so that the molten metal does not penetrate or cause sand erosion during pouring. After the coating dries, the cluster is placed into a flask and filled with bonded sand, the flask need to be vibrated during filling of sand to obtain proper compaction. Molten metal is then poured into the mould, the pattern vaporizes, and the cavity is filled and replaced by metal.