Ring forging is a part that is formed at a certain pressure and speed after the billet is heated by the die. In the process of ring forging, due to plastic deformation and thermal expansion of the material, internal stress and microstructure defects will occur. Therefore, in order to improve the mechanical properties and service life of ring forgings, heat treatment is required.
The heat treatment process of ring forgings usually includes annealing, normalizing, quenching and tempering steps. The specific selection and control depends on the nature and requirements of the material, the size and shape of the part, and the desired mechanical properties.
- Annealing: Annealing is the process of heating the ring forgings to a certain temperature and cooling them slowly after a period of time. Annealing can eliminate the internal stress generated during the forging process, improve the plasticity and toughness of the material, and adjust the organizational structure.
- Normalizing: Normalizing is to heat the ring forging to the appropriate temperature and cool it to room temperature after holding it for a period of time. Normalizing can further improve the strength and hardness of ring forgings, improve the wear resistance and fatigue resistance of materials.
- Quenching: Quenching is the process of heating the ring forgings above the critical temperature and maintaining them for a period of time. Quenching can make the material produce martensitic structure, improve the hardness and strength of ring forgings, but at the same time lead to increased brittleness.
- Tempering: Tempering is to heat the ring forgings to the appropriate temperature after quenching, and cool them at the appropriate rate after maintaining them for a period of time. Tempering can reduce the microstructure brittleness caused by quenching and improve the toughness and machinability of ring forgings.
The effect analysis of heat treatment includes the following aspects:
- Organizational structure: Heat treatment can change the organizational structure of ring forgings, and different organizational morphology can be obtained by controlling heat treatment parameters, such as austenite, pearlite, bainite, etc. The mechanical properties and durability of ring forgings are significantly affected by different structure.
- Strength and hardness: Heat treatment can improve the strength and hardness of ring forgings, through reasonable selection and control of heat treatment process, can make ring forgings to meet the design requirements of strength and hardness indicators.
- Toughness and toughening effect: The appropriate heat treatment process can improve the toughness of ring forgings and reduce their brittleness. The tempering process can further improve the toughness of ring forgings and make them have good impact resistance and fracture toughness.
- Dimensional stability: Heat treatment can adjust the size and shape of the ring forging, by controlling the heat treatment parameters, you can make the ring forging to meet the design requirements of the accuracy and dimensional stability.
In a word, the mechanical properties, durability and reliability of ring forgings can be significantly improved by reasonable selection and control of heat treatment process. At the same time, the heat treatment process also needs to be optimized and adjusted according to the specific material and part requirements to obtain the best results.
