THE FORGING PROCESS

Forging is a metal forming process used to produce large quantities of identical parts, as in the manufacture of automobiles, and to improve the mechanical properties of the metal being forged, as in aerospace parts or military equipment. The design of forged parts is limited when undercuts or cored sections are required. All cavities must be comparatively straight and largest at the mouth, so that the forging die may be withdrawn. The products of forging may be tiny or massive and can be made of steel (automobile axles), brass (water valves), tungsten (rocket nozzles), aluminum (aircraft structural members), or any other metal. This process is also used for coining, but with slow continuous pushes.
The forging metal forming process has been practiced since the Bronze Age. Hammering metal by hand can be dated back over 4000 years ago. The purpose, as it still is today, was to change the shape and/or properties of metal into useful tools. Steel was hammered into shape and used mostly for carpentry and farming tools. An axe made easy work of cutting down trees and metal knives were much more efficient than stone cutting tools. Hunters used metal-pointed spears and arrows to catch prey. Blacksmiths used a forge and anvil to create many useful instruments such as horseshoes, nails, wagon tires, and chains.
Militaries used forged weapons to equip their armies, resulting in many territories being won and lost with the use and strength of these weapons. Today, forging is used to create various and sundry things. The operation requires no cutting or shearing, and is merely a reshaping operation that does not change the volume of the material.
Forging changes the size and shape, but not the volume, of a part. The change is made by force applied to the material so that it stretches beyond the yield point. The force must be strong enough to make the material deform. It must not be so strong, however, that it destroys the material. The yield point is reached when the material will reform into a new shape. The point at which the material would be destroyed is called the fracture point.