Forging is a manufacturing process involving the shaping of various metals using localized compressive forces. The blows are delivered with a hammer or die, basically pressing and squeezing the metal using a large amount of pressure. The forging process can create metal parts that are stronger than any other metal working process.
There are various forging methods such as:
Impression Die Forging: Impression die forging pounds or presses metal between two dies that contain a pre-cut profile of the desired part.
Cold forging: Most forging is done as hot work, however cold forging is a variation that encompasses many processes to yield a more diverse range of part shapes.
Open die forging: This is performed between flat dies with no pre-cut profiles; larger parts can be hammered or pressed into shape this way.
Seamless rolled ring forging: This is typically performed by punching a hole in a thick piece of metal; this is then rolled and squeezed creating a donut shape.
Upset Forgings: This is achieved by positioning a pre heated bar into a groove to hold it in place, adding pressure then reforming it into the shape of the mould.
Hand Forgings: These are performed by skilled workers by hand using traditional methods
Drop Forgings: This is achieved by compressing pre heated material between two dies and through a sequence of production steps can be made into the desired shape.
The art of forging techniques dates back to at least 4000 BC. Fire in the early days was utilized as a heat and light source, it was also used as against the wild animals as a protection shield and was used to cook food. It was soon discovered that precious metals like gold, silver and copper could be given a distinct shape with fire; this is how the craft of forging metals was invented. Bronze and iron also went through the forging process to produce tools, weapons and jewellery.
There are many metals that can be used in forging today, such as aluminium, brass, carbon steel, copper alloy steel, bronze and stainless steel. Physical properties such as strength and toughness are much better after a metal has been forged. Forging is superior to casting or machining bar stock because the metals natural grain flow is made to conform to the shape of the product.
Nowadays the forging industry skilfully produces a wide range of forged steel tools for use in the aerospace, automotive, agriculture and energy industries. Forged parts help assemble things you can rely on on a day to day basis such as airplanes, engines, tractors and ships to name just a few.
The forging process is superior to casting or machining bar stock because the metals natural grain flow is made to conform to the shape of the product. Forgings are superior in tensile and shear loads due to the utilization of the grain flow. Forgings can be nearly any shape, this reduces the need for joining multiple pieces, reducing the joint can improve overall strength of the unit as the forging does not need to be welded or fastened together. Forging is more reliable and generally cheaper in total cost than casting or fabrication.
Tools of the trade include the hammer and anvil, tongs, chisels and swage blocks, not forgetting the forge where you will actually heat up your work.