The correct selection and implementation of metal surface heat treatment materials will directly affect the performance, service life, and safety of various mechanical products, and play an important role in the development of new products and improving product competitiveness. Especially for automotive metal accessories, it has a unique position in the application and improves many problems existing in surface heat treatment, effectively improving the quality of workpieces. We hope to improve the quality of metal surface heat treatment materials and provide support for the improvement and development of automotive metal accessories.

Application of surface treatment

1. Improve aesthetics: Surface treatment can make the surface of metal accessories brighter and improve the aesthetics of the product. For example, exposed metal parts such as car logos, bumpers, door handles, window frames, and wheel hubs can be made brighter and more beautiful after chrome plating, zinc plating, etc.

To achieve the effect of heat treatment on the metal surface, it is necessary to reasonably adjust the ratio of gas and oxygen (usually 1:4-1:3) and keep the gas pressure in the combustion chamber stable to ensure uniform heating and achieve better completion of metal surface heat treatment to achieve the desired effect. Reasonable gas ratio is conducive to promoting the implementation of metal surface heat treatment, and plays an important role in the aesthetics of the metal surface, achieving the expected or even higher expected effect. Parts processing helps to improve the performance indicators of the whole vehicle, thereby improving the power performance, and energy-saving and environmental protection performance of the whole vehicle.

2. Improve performance: Surface treatment can significantly improve the performance of metal accessories. For example, carburizing and nitriding treatment of moving parts such as pistons, piston rings, and connecting rods in engines can improve the hardness and wear resistance of the surface while maintaining the plasticity and toughness of the core; bolts, screws, nuts, etc. are fastened Parts can be treated with zinc plating, nickel plating, etc. to improve corrosion resistance and oxidation resistance.

When the metal surface solidification layer is deep, the speed is slow, and when the solidification layer is thin, the speed is fast. According to the actual situation, the moving speed should be scientifically selected and positive and effective measures should be taken to scientifically handle the relationship between the nozzle and the workpiece. Selecting a suitable nozzle is to improve the application of metal surface heat treatment process technology to meet higher process requirements.

In the field of modern automobile manufacturing, there are extremely high requirements for the dimensional accuracy and surface quality of parts. Therefore, it is necessary to apply cutting-edge processing technology and testing methods. Through precise control of the processing process, it can not only reduce the scrap rate caused by dimensional deviation but also shorten the assembly cycle, thereby improving the production efficiency of the whole vehicle. This is the key link in the processing of parts to improve the performance, quality, and production efficiency of the whole vehicle.

3. Anti-corrosion protection: Anti-corrosion spraying is widely used on metal parts of automobiles. By spraying anti-corrosion paint on the surface of metal parts such as the car body and wheels, a protective film is formed to isolate the metal from the external corrosive medium and prevent the metal parts from rusting and corrosion. For example, the car body primer spraying has an anti-corrosion function to prevent the car body from being corroded during subsequent processing and use.

For metal surface heat treatment, the water temperature should not be too low to avoid cracking, usually at 15-18℃; and annealing is carried out quickly. The annealing temperature is generally 180~220℃ for one hour to reasonably control the surface quality of the workpiece. After appropriate chemical treatment, it is packaged and infiltrated. The infiltration temperature is 850-870℃, and it is pre-cooled to 820℃ after quenching for 2-4 hours for direct quenching. Due to the quenching temperature being too low or the holding time being insufficient, the core remains in the block ferrite. This ferrite usually causes uneven oxidation and stains even when the surface is in contact. To ensure that the contact points between the workpieces are reduced or less tightly packed on small parts for flipping, processing during the oxidation process can reduce the degree of oxidation, thereby increasing the service life of metal accessories.

4. Adapt to different materials and strengths: For different mold materials and strengths, automobile manufacturers use different surface treatment technologies. For example, chrome plating technology is commonly used on ordinary steel plate molds, while high-strength steel plates use technologies such as TD and PVD. These technologies can not only effectively suppress hair pulling, but also extend the life of the mold and improve the quality of stamping parts.

During the heating process, the oxidation and decarburization of the metal due to the chemical reaction of the surrounding heating medium and the metal surface seriously affect the quality of the quenched workpiece. Because different metal materials will produce different effects, and the results presented are completely different. Oxidation: refers to the process in which oxygen, oxidizing gases, and impurities in the heating medium on the surface of the metal oxidize to form iron oxide. Decarburization: Decarburization means that the carbon in the surface layer of the metal is oxidized, so the carbon content in the surface layer of the metal is reduced. The higher the heating temperature of the metal, the higher the carbon content of the metal (especially the high content of silicon, platinum, aluminum, etc.). The easier it is to decarburize the metal.

In order to avoid oxidation and decarburization, protective atmosphere heaters, vacuum heaters, and heaters can be used together with packaging for surface-coated workpieces according to the technical requirements and actual conditions of the workpiece. To protect the surface quality of the heated workpiece, the surface quality can be greatly improved, thereby increasing the strength.

5. Multi-factor considerations: The choice of surface treatment requires comprehensive consideration of multiple factors such as mold material, material strength, processing temperature, time, and performance requirements. Optimizing these process parameters can reduce costs, improve production efficiency, and ensure product quality.

With the accumulation of data and continuous optimization of models, the system's prediction and control of the surface treatment of metal accessories will become more accurate. Precise regulation of processing parameters is the core of improving the processing accuracy of automotive parts. By using technologies such as experimental design, adaptive control, and machine learning, a quantitative model between process parameters and processing accuracy can be constructed, thereby achieving precise control of the processing process and ensuring that the dimensional tolerance of parts is within the specified range.

Monitoring and diagnosis of the status of surface treatment machine tools is also an important technology to ensure the machining accuracy of automotive parts. The use of advanced measuring instruments to regularly detect the geometric accuracy of machine tools and analyze their changing trends in combination with mathematical models will improve real-time monitoring and intelligent diagnosis, which is the key to ensuring the machining accuracy of automotive parts and provides strong support for parts processing.