forge et fonderie

Sand casting iron

The cast iron consists of metal alloy made essentially of iron and at least 2% carbon. Adding elements such as chrome or nickel makes the iron more resistant to corrosion and oxidation.
Lamellar casting and spheroidal casting are the most widely used irons. Their hardness is usually higher to the one of steels which makes them suitable for applications where rigidity is important.

The process generally involves remelting pig iron initially obtained from the ore process (blast furnace process) which is refined to suit the desired grade. Foundry scrap is also often added.

The liquid metal is poured into sand moulds. These are made by pressing a shape into the sand using a pattern or tool (made of wood or aluminium).



Two half-imprints are made, each corresponding to half the piece, then they are put together to create the mould.

Sand moulds are made either in metal chassis or in single-use pits at a manual site (for pieces up to dozens of tons) or automated moulding lines. The melt, preferably prepared in a cupola, is poured as needed, per piece and per type of melt. Left to cool in free air, the pieces are then removed from their sand envelope.

Additional operations such as milling, sand blasting, painting and machining can then be done.

Materials used in Sand casting iron