Metal Forming has been done for thousands of years. From early man making knives and spear heads from iron meteorites, found on the ground from falls, and bronze items both artistic and functional. Some of the earliest metal forming was from native gold and silver, examples being discovered in Egyptian tombs, Etruscan, and Viking burial sites and Aztec, Mayan, and Peru archeological excavations. Weapons such as swords made by the Japanese were incredibly advanced. Metal Forming methods ranged from, hot and cold forging to casting were employed.
During the Industrial Revolution, more sophisticated methods were discovered and created. Casting and Forging processes aided the on-coming of mass production. Machining techniques became more mechanized and turning lathes, and milling machines came into being, increasing productivity and part repeatability for better quality products. This ability reduced costs, making more products within the reach of the average individual, improving the quality of life.
With the advent of flight, modern aircraft caused more advancement for the forming of metals. Large forming presses formed and stamped out wing skins and other more complex shapes, which in earlier times were created by hand over templates and wooden forms. Turning and milling machines also became capable of machining enormous parts to close tolerances.
Today many exotic and complex shapes are hot formed in metal dies at high temperatures and pressures, making the forming of exotic metals a reality. Another method is Deep Draw Forming in a hydraulic press using single or multiple dies to achieve the desired shape. A similar approach is Hydro-forming, which uses a rubber bladder to force the metal blank through a die.
Using the described techniques, high strength metals such as Titanium, Heat Treatable Stainless Steel Alloys, and Nickel Based Alloys can be formed into many shapes. These metals are utilized in the Aerospace and Defense industries where light weight and strength are a must. An even more exotic process, Explosive Forming is used for more complicated forming operations. This process is accomplished in an enclosed die, and the forming is done using a shape charge, to form the part explosively with the high pressure generated by the charge.
As we move forward into the 21st Century, no doubt even more sophisticated metal forming methods will be developed, to continue this most important area of manufacturing endeavors.