forging process

      Forging is the process by which metal is heated and is shaped by plastic deformation by suitably applying compressive force. Usually the compressive force is in the form of hammer blows using a power hammer or a press.

       Forging refines the grain structure and improves physical properties of the metal. With proper design, the grain flow can be oriented in the direction of principal stresses encountered in actual use. Grain flow is the direction of the pattern that the crystals take during plastic deformation. Physical properties (such as strength, ductility and toughness) are much better in a forging than in the base metal, which has, crystals randomly oriented.

        Forgings are consistent from piece to piece, without any of the porosity, voids, inclusions and other defects. Thus, finishing operations such as machining do not expose voids, because there aren't any. Also coating operations such as plating or painting are straightforward due to a good surface, which needs very little preparation.

Forgings yield parts that have high strength to weight ratio-thus are often used in the design of aircraft frame members.

A Forged metal can result in the following

•	Increase length, decrease cross-section, called drawing out the metal.
•	Decrease length, increase cross-section, called upsetting the metal.
•	Change length, change cross-section, by squeezing in closed impression dies. This results in favorable grain flow for strong parts  Common Forging Processes The metal can be forged hot (above recrystallization temperatures) or cold. Open Die Forgings / Hand Forgings:      Open die forgings or hand forgings are made with repeated blows in an open die, where the operator manipulates the workpiece in the die. The finished product is a rough approximation of the die. This is what a traditional blacksmith does, and is an old manufacturing process. Impression Die Forgings / Precision Forgings:        Impression die forgings and precision forgings are further refinements of the blocker forgings. The finished part more closely resembles the die impression.