The essence of metal forging processing is to use the plasticity of metal and its ability to produce plastic deformation. With the help of tools or dies, under the action of external impact or pressure, the blank is formed into a certain shape, size, internal structure and mechanical properties. A method of processing mechanical parts or blanks that meet the requirements.

Compared with metal casting, welding, and cutting processing methods, forging processing has the following characteristics.

1. The structure and performance of forgings are improved. After forging, the internal structure of metal undergoes significant changes. For example, steel ingots produced by steelmaking often have defects such as looseness, coarse grains, uneven structure, and segregation of components. The structure is loose after forging and other pressure processing. The forging is obtained, the interior is dense, the coarse dendrites are broken, the crystal grains are refined, and the segregation is improved. The forging formed by the blank forging has good shape and dimensional stability, reasonable fiber structure, refined structure, improved distribution of the second phase, and greatly improved the plasticity, impact toughness, and fatigue properties of the forging. The performance changes between forgings are small.

2. High material utilization. Forging processing is the use of metal in a plastic state through volume transfer to achieve forming, to obtain forgings of a certain shape and size, without cutting, only a small amount of process waste, and high material utilization.

3. High dimensional accuracy. The workpieces obtained by metal forging can achieve high dimensional accuracy, the machining allowance of forgings is small, and many forging forming methods have reached the requirements of little or no cutting. For example, precision forged bevel gears can be used directly without cutting, and the complex curved surfaces of precision forged blades can reach the precision that only requires grinding.

4. Flexible forging process, both single piece production and mass production, high productivity. For free forging, small batch or single piece forging production can be carried out. At present, free forging is the main forging processing method for large forgings. For die forging, due to the continuous development of forging processing equipment and the improvement of mechanization and automation, die forging production has high production efficiency and is suitable for mass production. For example, it only takes 40s to forge a six-turn crankshaft for an automobile on a 120000kN hot die forging press; the high-speed punch stroke in the forging process has reached 1500-1800 times/min; forging and processing M5mm screws on the planetary thread rolling machine, production The efficiency is as high as 12000 pieces/min.