Forging is a processing method that uses a forging machine to apply pressure to the metal blank to plastically deform it to obtain a forging with certain mechanical properties, certain shape and size.
By forging, defects such as as-cast looseness during the metal smelting process can be eliminated, and the microstructure can be optimized. At the same time, due to the preservation of the complete metal streamline, the mechanical properties of forgings are generally better than those of castings in the same material.
According to the forging temperature, forging technology can be divided into Hot Forging, warm forging and cold forging.
The initial recrystallization temperature of steel is about 727 °C, but 800 °C is generally used as the dividing line, and hot forging is higher than 800 °C; between 300 and 800 °C, it is called warm forging or semi-hot forging; forging at room temperature is called cold forging. Forgings used in most industries are hot forging; warm forging and cold forging are mainly used in automobiles and general machinery, and warm forging and cold forging can effectively save materials.
Forging materials are mainly carbon steel and alloy steel of various compositions, following is aluminum, magnesium, copper, titanium, etc. and their alloys. Iron-based superalloys, nickel-based superalloys, and cobalt-based superalloys are also used for forging or rolling, but these alloys are relatively difficult to forge due to their relatively narrow plastic zone. The heating temperature, opening forging temperature and final forging temperature of different materials have different strict requirements.
