Metal casting is the process of turning molten metal into a solid shape. At the simplest level, this could mean casting a basic shape called an ingot, whose final form and mechanical properties will be refined by forging. At its more difficult level, it could mean producing a component of complex geometry as a near-net shape part required minimal machining.
The metal (sand) casting process can be explained in five simple steps –
Pattern-making – A pattern is a replica of the exterior of the casting with the patterns typically made of metal, wood, plastic or plaster. This process is extremely important for industrial part-making where precise calculations are required to make pieces fit and work together.
Core-making – If a casting is hollow an additional piece of metal or sand (referred to as a core) shapes the internal form, making it hollow. Cores are strong but collapsible, meaning they can be easily removed from the finished casting.
Molding – Molding is a multi-step process which forms a mold around the pattern using molding sand. In casting the mold that is contained in a frame is referred to as a flask. Green sand (or molding sand) is packed into the flask around the pattern. An alternative option is a two-piece, non-destructible metal mold can be created and then used repeatedly to cast identical parts for various industrial applications.
Melting and Pouring – Once liquid metal is melted it is poured into the mold and left to solidify. Once this process is complete, the shakeout process begins where the molds undergo vibration which removes sand from the casting. The removed sand is typically collected, cooled and reclaimed for use in future castings.
Cleaning – The cast metal object is now removed from the mold and then fettled, where it is cleaned of any molding material and any rough edges are removed.
If you have any more questions about sourcing cast components in austenitic or duplex stainless steels, nickel alloys or high-performance copper alloys, please contact us today. A member of our team will be more than happy to help and can also advise you on the best option for your application.