Casting Processes
A look into Melting and
Casting Metal
Metal Casting
Create liquid metal - Melting
Combustion used to melt material
Electricity used to melt material
Create solid shape - Casting
Permanent mold casting
Semi Permanent mold casting
Consumable mold casting
Oxy-fuel Furnace
Uses a fuel gas such as propane, natural
gas or acetylene
Oxygen or atmosphere is blown in and
combined with fuel
Heat from combustion melts the charge
Oxy-fuel Furnace
Resistance Furnace
A current passed through a material
resulting in ohmic heating
Radiation heats charge material
Some convection and conduction occurs
Resistance Furnace
Induction Furnace
A current is passed through a water
cooled coil near or around the charge
Eddy currents are produced in the charge
material in response to the coil current
Heat is generated through ohmic heating
in the material
Induction Furnace
Electric Arc Furnace
A current is passed from separate
electrodes creating arcs of ionized gas
Heat is transferred from the arc into the
charge material
Can be either DC or AC
Electric Arc Furnace
Permanent Mold Casting
Mold that can be used repeatedly
Commonly associated with die casting
Mold material varies with metal to be cast
Used for large number of pieces to be
cast due to initial cost of the mold
Permanent Mold Casting
Continuous Casting
A water cooled mold is used to make a
long casting of constant cross section
Liquid metal is poured into the mold
against a starter block
As the metal solidifies it is removed
exposing more liquid to the mold face
Continous Casting
Semi-permanent Casting
A mold is made with both permanent and
single use parts
Consumable parts are usually cores
made of chemically bonded sand
After each pour the mold is cleaned and
new consumables are added
Semi-permanent Casting
Investment Casting
A refractory material (investment) is
poured around or built up on a pattern
The investment is hardened by drying or
heating
The pattern is removed by m