Knowledge about forging

A forging machine is used to apply pressure to a metal blank to cause plastic deformation to obtain a forging having a certain mechanical property, a certain shape and size. One of the two major components of forging (forging and stamping). Forging can eliminate defects such as as-cast looseness caused by metal in the smelting process, optimize the microstructure, and at the same time, the mechanical properties of the forgings are generally superior to those of the same materials due to the preservation of the complete metal flow lines. For important parts with high load and severe working conditions in machinery, forgings are often used except for rolled sheets, profiles or welded parts that are simple in shape. Forging can be divided into: 1 free forging according to the forming method. The impact force or pressure is used to deform the metal between the upper and lower two irons (anvil) to obtain the required forgings, mainly hand forging and mechanical forging. 2 die forging. Die forging is divided into open die forging and closed die forging. Metal blanks are pressed and deformed in a forging die with a certain shape to obtain forgings, which can be divided into cold heading, roll forging, radial forging and extrusion. Wait. Forging at deformation temperature can be further divided into hot forging (forging temperature is higher than recrystallization temperature of billet metal), warm forging (forging temperature is lower than metal recrystallization temperature) and cold forging (normal temperature). The materials for forging are mainly carbon steel and alloy steel of various compositions, followed by aluminum, magnesium, titanium, copper and the like and alloys thereof. The raw state of the material is bar, ingot, metal powder and liquid metal. The ratio of the cross-sectional area of ​​the metal before deformation to the cross-sectional area after deformation is called the forging ratio. Correct selection of forging ratio, reasonable heating temperature and holding time, reasonable initial forging temperature and final forging temperature, reasonable deformation amount and deformation speed have a great relationship to improve product quality and reduce cost.