Casting methods
The metal casting process begins by creating a mold, which is the ‘reverse’ shape of the part we need. The mold is
made from a refractory material, for example, sand. The metal is heated in an oven until it melts, and the
molten metal is poured into the mold cavity. The liquid takes the shape of a cavity, which is the shape of the
part. It is cooled until it solidifies. Finally, the solidified metal part is removed from the mold.
A large number of metal components in designs we use every day are made by casting. The reasons for this
include:
(a) Casting can produce very complex geometry parts with internal cavities and hollow sections.
(b) It can be used to make small (few hundred grams) to very large size parts (thousands of kilograms)
(c) It is economical, with very little wastage: the extra metal in each casting is re-melted and re-used
(d) Cast metal is isotropic – it has the same physical/mechanical properties along any direction.
Common examples are door handles, locks, the outer casing or housing for motors, pumps, etc., and wheels of many
cars. Casting is also heavily used in the toy industry to make parts, e.g. toy cars, planes, and so on.
For further details, please visit the link:
http://www.pfa.org.pk/wp-content/uploads/2017/04/Basics-of-Metal-Casting-1.pdf
