Hot forging and cold forging are two different metal forming processes that deliver similar results. Forging is the process of deforming metal into a predetermined shape using certain tools and equipment—deformation is accomplished using hot, cold, or even warm forging processes. Ultimately, the manufacturer will look at a number of criteria before choosing which type of forging is best for a particular application.

• Up to 1150 degrees Celsius for Steel
• 360 to 520 degrees Celsius for Al-Alloys
• 700 to 800 degrees Celsius for Cu-Alloys

During hot forging, the temperature reaches above the recrystallization point of the metal. This kind of extreme heat is necessary in avoiding strain hardening of the metal during deformation. In order to prevent the oxidation of certain metals, like super alloys, a type of hot forging called isothermal forging is a good choice. In isothermal forging, the metal deformation occurs within a highly controlled atmosphere, similar to that of a vacuum.

• Less precise tolerances
• Possible warping of the material during the cooling process
• Varying metal grain structure
• Possible reactions between the surrounding atmosphere and the metal