Forging is an important part in the process of metal material manufacturing, and its processing quality directly affects the performance and service life of the product. In the forging process, heat treatment technology, as a key step to improve the internal structure of metal materials and improve material properties, has been concerned by the majority of engineers and technicians. This paper will study the heat treatment technology in forging process, in order to provide reference for engineers and technicians in related fields.
Principle and function of heat treatment technology
Heat treatment technology refers to a process method by heating, insulation and cooling to make the metal material undergo a structural transformation in the solid state, so as to obtain the expected performance. In the forging process, heat treatment technology is mainly used to improve the physical properties of the material such as plasticity, toughness and strength, as well as to eliminate the internal stress of the material, refine the grain, and improve the processing performance of the material.
Specifically, the role of heat treatment technology is mainly manifested in the following aspects:
Eliminate internal stress: The forging will produce internal stress during processing, which will lead to deformation, cracking and other problems in the subsequent use of the material. Through heat treatment technology, plastic deformation of the material can occur during the heating process, thereby eliminating the internal stress and improving the stability of the material.
Fine grain: During the heat treatment process, the material will recrystallize at high temperatures, making the grain fine. The refined grain is helpful to improve the strength and toughness of the material and improve the comprehensive properties of the material.
Adjusting material properties: By adjusting parameters such as heating temperature, holding time and cooling speed during heat treatment, accurate control of material properties can be achieved. For example, quenching treatment can improve the hardness and wear resistance of the material, tempering treatment can reduce the brittleness of the material and improve the toughness.
Heat treatment technology in forging process
In the forging process, the commonly used heat treatment technology mainly includes annealing, normalizing, quenching and tempering.
Annealing: Annealing is the process of heating the forging to a certain temperature after holding it for a period of time, and then slowly cooling it. Annealing can eliminate the internal stress of the material, reduce hardness, improve plasticity and toughness, and improve the processing performance of the material. Common annealing methods include complete annealing, incomplete annealing and spheroidizing annealing.
Normalizing: Normalizing is the process of heating the forging to a certain temperature above the critical point, holding it for a certain time, and cooling it in free air. Normalizing can improve the strength and toughness of the material and improve the cutting performance of the material.
Quenching: Quenching is the process of heating the forging to a certain temperature above the critical point, and after holding for a certain time, cooling at a cold speed greater than the critical cooling speed. Quenching can significantly improve the hardness and wear resistance of the material, but it also increases the brittleness of the material. In order to reduce the brittleness after quenching, tempering treatment is usually required.
Tempering: Tempering is the process of heating the quenched forging to a certain temperature after holding it for a period of time, and then cooling it. Tempering can eliminate the internal stress generated by quenching, reduce the hardness and brittleness of the material, and improve the toughness and plasticity of the material. According to the different tempering temperature, it can be divided into low temperature tempering, medium temperature tempering and high temperature tempering.
Optimization and innovation of heat treatment technology
With the continuous progress of science and technology and the rapid development of manufacturing, heat treatment technology is also constantly optimized and innovative. On the one hand, through the precise control of heating temperature, holding time and cooling speed in the heat treatment process, the precise control of material properties can be achieved. On the other hand, the use of new heat treatment equipment and process methods, such as vacuum heat treatment, laser heat treatment, etc., can further improve the efficiency and quality of heat treatment.
Heat treatment technology is an important link in the forging process, which plays an important role in improving material properties and product quality. With the continuous progress of science and technology and the rapid development of manufacturing, heat treatment technology is also constantly optimized and innovative. In the future, we should continue to strengthen the research and application of heat treatment technology to provide strong support for the development of manufacturing.
