Forging forming -- English · 2023年10月12日 0

Surface treatment technology for forging production

As an important part in mechanical manufacturing, the surface quality of forgings directly affects the performance and service life of products. In order to improve the surface quality of forgings and meet the performance requirements of products, appropriate surface treatment technology must be adopted in the production process of forgings. This paper will introduce the surface treatment technology of forging production in detail, and analyze its influence on the quality of forging.

The surface treatment technology of forging production mainly includes heat treatment, chemical treatment, electroplating treatment and so on. These processing technologies have their own characteristics and are suitable for different forging materials and performance requirements.

Heat treatment: Heat treatment is a process method to change the internal organization and properties of metal materials by means of heating, insulation and cooling. In the production of forgings, the commonly used heat treatment techniques include annealing, normalizing, quenching and tempering. Heat treatment can adjust the mechanical properties of materials, improve the hardness and wear resistance of forgings, while reducing residual stress and reducing the possibility of deformation and cracking.
Chemical treatment: Chemical treatment is the use of chemical reactions on the metal surface to form a protective film layer to improve the corrosion resistance and wear resistance of forgings. Common chemical treatment methods include phosphating, oxidation, passivation and so on. These treatment methods can form a dense chemical conversion film on the surface of the forging, isolating the contact between the metal surface and the corrosive medium, so as to achieve the purpose of anti-corrosion.
Electroplating treatment: Electroplating treatment is the use of electrochemical methods to deposit a layer of metal or alloy coating on the surface of the metal to improve the wear resistance, corrosion resistance and beauty of the forgings. Common electroplating treatment methods include zinc plating, chromium plating, gold plating and so on. Electroplating treatment can give the forging surface excellent performance, while improving the appearance of the product quality.

In the forging production process, different surface treatment technologies need to be operated in accordance with specific process steps to ensure the treatment effect and quality. The following are the specific steps and precautions for some surface treatment technologies:

Heat treatment: In the heat treatment process, it is necessary to pay attention to the control of parameters such as heating temperature, holding time and cooling speed. The heating temperature is too high or too low, and the holding time is too long or too short, which may lead to the instability of the material structure and performance. The control of cooling speed is also crucial, too fast or too slow cooling speed may cause deformation or cracking of the forging. Therefore, the heat treatment process must be operated in strict accordance with the specified process parameters.
Chemical treatment: In the chemical treatment process, it is necessary to choose the appropriate chemical reagent and treatment temperature, and control the treatment time. Different chemical treatment methods have different requirements for the type and concentration of reagents, which must be selected according to the specific situation. The control of treatment temperature and treatment time will also affect the quality and performance of the chemical conversion film. Therefore, the chemical treatment process must be operated in strict accordance with the specified process parameters.
Electroplating treatment: In the process of electroplating treatment, it is necessary to pay attention to the control of parameters such as current density, bath composition, temperature and time. The current density directly affects the deposition speed and thickness of the coating, and the composition of the bath will affect the properties and appearance of the coating. The control of temperature and time will also affect the crystalline structure and properties of the coating. Therefore, the electroplating process must be operated in strict accordance with the specified process parameters.

In order to ensure the quality of forging surface treatment, it is necessary to check and control the quality of the processed forging. The following are some commonly used quality control methods:
Appearance inspection: Observe the appearance characteristics of the forging surface such as color, gloss and roughness, and judge the quality of the surface treatment. The appearance inspection can be carried out visually or with a magnifying glass.
Hardness test: hardness tester is used to test the hardness of the forging surface to determine the effect of the heat treatment process and the hardness of the coating.
Corrosion resistance test: The forging is placed in the corrosive medium for corrosion resistance test to evaluate the chemical treatment effect and the corrosion resistance of the coating. It can be carried out by salt spray test and neutral salt spray test.
Other performance tests: According to the specific product requirements, other performance tests can also be carried out, such as wear resistance testing, binding force testing.

This paper introduces the surface treatment technology of forging production, including heat treatment, chemical treatment and electroplating treatment. These treatment techniques have an important impact on the surface quality and performance of the forging, and must be selected and applied according to the specific situation. In actual operation, it is necessary to pay attention to the control of process parameters and quality inspection to ensure the treatment effect and quality. In the future, with the continuous progress and development of science and technology, the surface treatment technology of forging production will also continue to improve and innovate, providing better support and services for the development of manufacturing industry.