Hot forging is a metal shaping process where a malleable metal part is known as a billet or workpiece. Such a portion is processed to obtain a predetermined shape. Here, procedures such as hammering, upsetting, or pressing are available; during these procedures, the workpiece is heated up to 75% at its melting temperature. The temperature of forging divides forging procedures into several categories such as hot forging, cold forging, and warm forging. Most metal components require hot forging.
What is hot forging?
Hot forging is the most widely used forging process. In the hot forging process,it requires a forging temperature above the temperature of metal recrystallization. In short, the temperature at which the new grains form in the metal.High temperature or extreme heat is essential for withdrawing strain hardening of the metal during its deformation process.
In actual conditions during industrial manufacturing, friction works a bit in the process. Here, friction forces at the die-work interface combat the spread of the material near the surfaces allows the expansion of central materials more efficiently. As a result, it creates a barrel shape; such an effect is called barrelling in metal forging. Barrelling is an undesirable phenomenon, and for its control, one can use adequate lubrication.
The hot forging manufacturing process increases the barrelling effect, also allows the heat to transfer between the hot metal and the cooler die. The metal more next to the die surfaces cool quicker than the metal present in the central part. The cooler material is more resistant to deformation and expands less. Whereas the hotter material deforms and expands also causes a barrelling effect.
Advantages of Hot Forging
It offers high strain rates and hence allows the easy flow of the metal. It will enable recrystallization and recovery procedures and requires fewer forces.
Applications of Hot Forging
Recrystallization is the process that involves the use of high temperatures. The procedure enhances formability and allows adjustment of a precise and fine-grained microstructure. The hot forging carries high strength and durability specified more than any other forming process. Also, it will enable hot die forging where high operating loads make unique component demands. These components are known as “Safety-Critical Parts”. The automotive and aerospace areas are the most important buyer markets for hot forgings.
Hot Forgings for the automobile application
Steel forging is a predominant process useful for automotive forging purposes. Wrought aluminum alloys are mostly helpful due to its increased lightweight construction demands, which reduced magnesium’s need. In the automobile industry, many small to medium-sized elements are forged under a closed die forging process. The process makes most automotive components with high strength and working performance. Several standard automotive forging products involve engine parts, the driving gear, powertrain, undercarriage, and brake system.
Hot Forgings in the aerospace industry
Fuselage components such as fittings for doors and wings, ribs, window frames requires forging. Along with this, an engine with turbine blades, propulsion cones, discs, control levers, fasteners, pins requires hot forgings. Rotor systems and its components depend on hot forging.
Steel forging is essential in the aerospace sector, which offers high-strength and temperature resistance to the material. Also, it allows the forging of nickel-based and titanium alloys as well as lightweight construction materials.
Other applications of hot forging
Besides automotive and aerospace applications, hot forging works well in several other areas. Furthermore, there are several other major application fields where hot forging shows its importance and strength. Industries like construction, mechanical engineering, agriculture, defense, steel production, and offshore sectors require hot forging.