-
-
-
-
Contact Us
Why do large forgings need to be heat treated after forging?
Release time:
2024-11-27
The purpose of heat treatment after forging large forgings is to refine the coarse grains caused during the forging process, eliminate work hardening and residual stress, reduce hardness, improve machinability, prevent the formation of white spots inside the forgings, ensure the desired metal structure and mechanical properties, and prepare for the final heat treatment.
The purpose of heat treatment after forging large forgings is to refine the coarse grains caused during the forging process, eliminate work hardening and residual stress, reduce hardness, improve machining performance, prevent the formation of white spots inside the forgings, ensure the desired metal structure and mechanical properties, and prepare for the final heat treatment. The commonly used methods include the following six.
Full annealing - eliminates the coarse and uneven structure and Widmanstätten structure caused during forging, refines the grains, and eliminates the residual stress of the forgings while reducing hardness.
Spheroidizing annealing - obtains spheroidal cementite and ferrite structure, which not only reduces hardness but also facilitates obtaining a smooth machined surface during cutting, and is less likely to produce deformation cracks during subsequent quenching.
Isothermal annealing - not only shortens the annealing time but also achieves a uniform structure and reduces hardness. In important large forgings, it can also be used to diffuse hydrogen gas to prevent the formation of white spots. The heat treatment of aluminum alloys and copper alloys after forging generally adopts the annealing process. The purpose is to eliminate work hardening and stress, and improve plasticity.
Normalizing - can obtain finer pearlite, which can improve the mechanical properties of the forgings and is suitable for machining.
Normalizing and high-temperature tempering - eliminates the stress generated during the cooling of normalizing, improving plasticity and toughness.
Quenching and tempering - gives large forgings good comprehensive mechanical properties.
More information
Contact Us
Add：No.1 Chuangye Road, Changjiang Town, Rugao City, Nantong City, Jiangsu Province, China
E-mail: 1483594405@qq.com