Forging is a metal shaping process by application of compressive forces using dies and tools. Following are the various types of Forging
1. Hot Forging– Forging process carried at a temperature above the recrystallization temperature of the metal is called hot forging. This process is done to prevent strain hardening during deformation
2. Cold Forging– Forging process carried at a temperature below the recrystallization temperature of the metal is called cold forging. This is done for simple shaped components preferably softer metals/alloys. Compared to cold forging, components produced by hot forging type are more ductile.
3. Press Forging– In press forging, a continuous pressure or force is applied, unlike the near-instantaneous impact of drop-hammer forging. In press forging, deformation of complete work-piece occurs while in drop-hammer forging, usually only the surfaces of the work piece in contact with the hammer and anvil deform; the interior of the work-piece remain relatively undeformed.
4. Drop Hammer Forging – It is a forging process where a hammer is lifted and then dropped onto the work-piece to deform it according to the die-shape.
There are two types of drop forging
a. open-die drop forging and
b. closed-die drop forging
In Open-die forging, the work-piece is not fully enclosed while in Close-die forging, the work-piece is fully enclosed.