steel forging
What is forging?
Upset forging: A method of forming and processing plastic parts, including workpieces, tools, or blanks, by applying external force to metal blanks (excluding plates) to cause plastic deformation, change size, shape, and improve performance.
Types and characteristics of steel forging

When the temperature exceeds 300-400 ℃ (blue brittle zone of steel) and reaches 700-800 ℃, the deformation resistance will decrease sharply and the deformation energy will be greatly improved. According to the forging performed in different temperature regions, according to the different forging quality and forging process requirements, it can be divided into three forming temperature regions: cold forging, warm forging, and hot forging. Originally, there was no strict limit on the division of this temperature region. Generally speaking, forging in a temperature region with recrystallization is called hot forging, and forging without heating at room temperature is called cold forging.

When low temperature forging, the dimensional change of the forging is small. Forging below 700 ℃, the formation of oxide scale is small, and the surface is not decarburized. Therefore, as long as the deformation energy is within the range of forming energy, cold forging can easily obtain good dimensional accuracy and surface finish. As long as the temperature and lubrication and cooling are controlled, warm forging below 700 ℃ can also obtain good accuracy. During hot forging, large forgings with complex shapes can be forged