According to the forming mechanism, forging can be divided into die forging, free forging, rolling ring, and special forging.
Die forging is divided into open die forging and closed die forging. The metal blank is pressed and deformed in a forging die having a certain shape to obtain a forged piece, and the die forging is generally used for producing a part with a small weight and a large batch size. Die forging can be divided into hot forging, warm forging and cold forging. Warm forging and cold forging are the future development directions of die forging, and also represent the level of forging technology.
According to the material, die forging can also be divided into black metal die forging, non-ferrous metal die forging and powder product forming. As the name implies, the materials are ferrous metals such as carbon steel, non-ferrous metals such as copper and aluminum, and powder metallurgy materials. Extrusion should be attributed to die forging and can be divided into heavy metal extrusion and light metal extrusion.
Closed die forging and closed upset forging are two advanced processes for die forging. Since there is no flash, the material utilization rate is high. Finishing of complex forgings is possible with one or several processes. Since there is no flash, the area of force applied to the forging is reduced and the required load is also reduced. However, care should be taken not to completely limit the blank. To this end, the volume of the blank is strictly controlled, the relative position of the forging die is controlled, and the forging is measured to reduce the wear of the forging die.