Forging is an ancient metalworking process where a metal is compressed under force into a desired shape. It can be done using a hammer and anvil and produces parts with good strength and toughness. There are different types of forging processes, including open-die forging using flat dies, impression-die forging where the workpiece takes the shape of shaped die cavities, and coining where parts are precisely forged without lubricants between dies. Forged parts often require additional heat treating for optimal properties.

1. Forging of Metals

2. Introduction
 A metal is shaped by compressive forces
 Oldest metal working process – 4000BC
 Can be performed with a hammer and anvil
 Typical forged products:
 Bolts
 Rivets
 Connecting rods
 Gears

3. Lading-gear components for
the C5A and C5B transport
aircraft, made by forging. Steps involved in forging a bevel
gear with a shaft.

4. Outline of Forging and Related Operations

5. Grain Structure
 Parts have good strength
 High toughness
 Forgings require additional heat treating
Fig : A part made by three different procedures, showing grain flow (a) casting (b) machining (c) forging

6. Open-Die Forging
 Is the simplest forging process
 Sizes can very from very small parts to very large parts

7. Open-Die Forging
 Upsetting or flat-die forgingUpsetting or flat-die forging – a solid workpiece is
placed between flat dies and is compressed
 Barreling
 caused by frictional forces at the die-workpiece
interfaces
 Can be minimized if a lubricant is used
 Thermal effects caused by barreling can be minimized
by using heated dies

8. Open-Die Forging
 Forging force

9. Impression-Die & Closed-Die Forging
 The workpiece acquires the shape of the die cavities while
being forged between the two shaped dies

10. Impression-Die & Closed-Die Forging
 The blank to be forged is prepared by:
 Cutting from a bar stock
 Preformed blank
 Casting
 Preformed blank from prior forging

11. Impression-Die & Closed-Die Forging
 Fullering & edging are used to distribute the
material
 Fullering – material is distributed away from an area
 Edging – material is gathered into an area
 Blocking – rough shaping of the part
 Impression dies – give the part its final shape

12. Precision ForgingPrecision Forging
 Used for economic reasons
 The part formed is close to the final dimensions
 Less machining is needed
 Higher capacity equipment is needed
 Aluminum and Magnesium alloys work well in the process

13. CoiningCoining
 Closed-die forging process
 Used for minting coins, medallions, & jewelry
 Lubricants can not be used in coining
 Can be used to improve surface finish

14. THE END