Metal forming is a chip less manufacturing process that involves various types of processes such as hot and cold rolling, forging, metal stamping, pressure die casting, powder metallurgy, sintering, foundry work, sand casting, die casting, investment casting, smithy work, metal forging and sheet metal fabrication. Depending on the process, the product may be near the net-shape or may require further processing.
In addition to the above processes and equipment, a metal forming shop may use various types of machine tools such as drilling, jig boring, turning, and grinding, etc. Metal forming is used to produce finished and semi-finished products for items such as: automobiles, processing plants, and the aerospace industry, etc. Metal-formed parts can be heat treated and surface treated with chemicals that protect the parts from corrosion, wear resistance and painted per the specifications.
There are three basic types of metal forming which are hot working, warm working, and cold working. Hot working is used when the metal is ductile, which means it is above recrystallization temperature. This method provides a faster production speed on items such as screws and bolts. In the hot working stage, metal bars and metal sheets can handle numerous methods such as perforating, shearing, bending, and punching. The item can then be cold formed for a precise finish, as hot working cannot do this.
Warm forming is performed above room temperature, but below melting temperature. This method requires less force and power than cold forming does and it can produce greater precision on intricate shapes. However, you can’t change the shape of the object as much as you can in hot forming.
Cold forming takes place at room temperature and it is usually done after initial shaping is done by heating the metal. Cold forming is generally more accurate than the other methods, but more power is required to perform it.
Depending on the complexity of the component, metal forming can be used for batch production or a single, one-off component. Metal forming is a highly skilled area and special metal forming shops with the right equipment, gauging tools and personnel are required for it to be successful. A good tool room for maintaining the various rolls and forming tools is also necessary.