Forging casting annealing

The purpose of heat treatment after forging is to refine the coarse grains caused by the forging process, eliminate work hardening and residual stress, reduce hardness, improve cutting performance, prevent white spots from forming inside the forging, and ensure the desired metal structure. And mechanical properties, ready for the final heat treatment. There are six commonly used ones.

Complete annealing - Eliminates coarse uneven microstructure and Widmannstatten structure caused during forging, refines the grain and eliminates residual stress and hardness of the forging.

Spheroidizing annealing - Obtaining spherical cementite and ferrite structure, which not only has a low hardness, but also is easy to obtain a smooth processed surface during cutting, and is less prone to deformation cracking in subsequent quenching.

Isothermal annealing - Not only shortens the annealing time, but also obtains uniform structure and reduces hardness. In important forgings, it can also be used to diffuse hydrogen to prevent white spots from forming. The post-forging heat treatment of aluminum alloys and copper alloys is generally performed by an annealing process. The purpose is to eliminate work hardening, stress, and plasticity.

Normalizing - Finer pearlite can be obtained, which can improve the mechanical properties of forgings for machining.

Normalizing and high temperature tempering - Eliminates the stress generated during normalizing cooling and improves plasticity and toughness.

Quenching and tempering - Forgings have good comprehensive mechanical properties.