What Is the Difference Between Rolling and Forging, and Which Is Better?

Rolling Process 

The metal blank passes through the gap (of various shapes) between a pair of rotating rolls. The pressure processing method, which reduces the section and increases the length of the material due to the compression of the roll, is the most commonly used production method of steel. It is mainly used for the production of profiles, plates, and pipes.

Forging Process 

It is a processing method that uses forging machinery to exert pressure on metal billet to produce plastic deformation and obtain forgings with certain mechanical properties, shapes and sizes. Forging is one of the two major components of forging and stamping. Through metal forging process, the defects such as as-cast porosity can be eliminated in the smelting process, and the microstructure structure can be optimized. At the same time, due to the preservation of complete metal streamline, the mechanical properties of forgings are generally better than castings of the same material. In the related machinery, in addition to the simple shape parts can be rolled plates, profiles or welding parts, the important parts with high load and severe working conditions almost adopt forgings.

Difference Between Rolling and Forging

(1) The difference between the axial and radial mechanical properties of forgings is smaller than that between those of rolled pieces. That is, the isotropy of forgings is much higher than that of rolled pieces, so the life of forged components is much longer than that of rolled pieces.

(2) In terms of the degree of deformation, the deformation degree of forgings is much greater than that of rolled pieces, that is to say, the effect of breaking eutectic carbides by forging is better than that by rolling.

(3) In terms of processing cost, the cost of metal forging is much higher than that of rolling. The forging process must be adopted for some key parts, workpieces bearing large load or impact, and workpieces with the complex shapes or very strict requirements.

(4) The forging has a complete metal streamline, and the integrity of the metal streamline is destroyed by the mechanical workers after rolling, which greatly shortens the life of the workpiece.