Laser technology was born in the early 1960s and is a highly developed high-tech. Its development and penetration have led to the development of other disciplines and technologies. Laser technology has become one of the main pillars of this century's high-tech industry. First, the characteristics of laser heat treatment technology Second, the application and development of laser heat treatment in industry Third, the development of new applications of laser heat treatment, promote the industrialization of laser processing As a flashlight manufacturer and wholesaler, we have many years of experience in producing and developing flashlights. 90% of our products are exported, and we have established partnerships with Wal-Mart, ALDI and other large supermarket chains, and we also supply to various professional outdoor tool companies, such as SBI, Carl Kammerling, etc. Our customers are all over Europe and America, and We are also slowly developing products for the Asian, African and Latin American markets. Led Torch,Led Plastic Torch,Plastic Handle Torch,Plastic Led Solar Torch Cangnan Younglite Electrical Co., Ltd. , https://www.younglitelight.com
Laser processing technology is the main application of laser technology in the industry. Laser processing technology has accelerated the transformation of the traditional processing industry, providing a new means of modern industrial processing technology, with great influence. Laser processing refers to cutting, heat treatment, welding, drilling, etc. of industrial parts with high-power laser beams. Compared with traditional processing methods, laser processing is characterized by: high concentration of laser beam energy and small processing area. The thermal deformation is small, the processing quality is high, the precision is high, the processed parts are not limited by size and shape, the cooling medium is not needed, and the pollution is small, the noise is small, the labor intensity is low, and the efficiency is high. The industrialization of laser processing technology is on the rise in China.
Laser heat treatment is a method of surface treatment of metal by using a high power density laser beam, which can realize phase change hardening (or surface hardening, surface amorphization, surface remelting), surface alloying, etc. The modification treatment produces a change in surface composition, texture, and properties that cannot be achieved by other surface quenching.
The laser has four characteristics of monochromaticity, coherence, directionality and high energy density, so its penetration ability is extremely strong. The penetrating power of the laser is determined by the intensity of its energy and the length of time. When the power density is from 103 W/cm 2 to 107 W/cm 2 , the metal surface is heated to a critical transition temperature lower than the melting point at a heating rate of 103 ° C / s to 107 ° C / s, and the surface is rapidly austenitized, and then rapidly Cold quenching, cooling rate up to 1.7 × 104 ° C / s, metal surface is quickly strengthened, which is laser phase transformation hardening.
The remarkable features of laser heat treatment are: high-speed heating, high-speed cooling, fine structure, high hardness and good wear resistance; residual compressive stress of more than 400kgf/mm2 can be obtained in the quenching part, which can improve fatigue performance; Local selective quenching, through the control of multi-spot size, is more suitable for hardening of local areas such as tube holes, deep grooves, micro-zones, angles and tool edges that other heat treatment methods cannot. Laser can be transmitted over long distances. A laser multi-workbench is used at the same time, and the computer control is used to realize the control and management of the laser heat treatment process to realize the automation of the production process.
Because laser heat treatment has obvious advantages, it solves the technical problem that traditional metal heat treatment can not solve or is not easy to solve. It has been highly valued at home and abroad, and laser heat treatment has been rapidly developed.
High-power CO2 lasers have developed rapidly since the 1970s, and high-power CO2 lasers in advanced industrial countries have been commercialized and serialized. China has successfully developed high-power CO2 multimode lasers from kilowatts to megawatts since the "seventh five-year plan". With the development of high-power lasers, various forms of surface treatment can be realized with a laser. It is a metallurgical process that causes changes in the structural structure of the material, and its heating time is in the range of 10-3 s to 10-7 s, and the power density is more than 0.1 kW per square millimeter. It is extremely versatile and can be applied to almost all metal surface heat treatments. At present, there are many industries that have serious wear and tear, such as automobiles, metallurgy, petroleum, heavy machinery, and agricultural machinery, as well as high-tech products such as aerospace and aviation.
Laser heat treatment is widely used in the automotive industry. In many automotive key parts, such as cylinders, cylinder liners, crankshafts, camshafts, exhaust valves, valve seats, rocker arms, aluminum piston ring grooves, etc., laser heat treatment can be used. . For example, the United States General Motors Corporation used a dozen kilowatt-class CO2 lasers to partially harden the inner wall of the commutator casing, with a daily output of 30,000 sets, which improved the work efficiency four times. China uses high-power CO2 laser to strengthen the inner wall of the cylinder bore of the automobile engine, which can extend the overhaul mileage of the engine to more than 150,000 kilometers, and one cylinder is equal to three untreated cylinders.
The wear resistance of the laser-heated cylinder block and the cylinder sleeve hardened belt is greatly improved. The unhardened belt can increase the oil storage and improve the lubrication performance. The tractors in China are developing rapidly, and new brands are constantly being introduced, but the internal combustion engine cylinders and cylinders for tractors With a short life span, serious damage and a large amount of maintenance, Xi'an Internal Combustion Engine Parts Factory, with the help of the State Science and Technology Commission, first built a laser heat treatment production line for diesel engine cylinder liners with an annual output of 600,000 and a life extension of 10,000 hours.
The laser heat treatment equipment and laser line of the cylinder body are similar to the laser alloying process, but the difference is that no additional alloy is added, so that the metal surface melts and then cools and solidifies, thereby obtaining a fine near uniform surface structure for some eutectic alloys. An amorphous surface layer is also obtained which has excellent corrosion resistance, for example, a chromium-based surface coating on a diesel engine cast iron seat to obtain a good stainless steel surface.
Laser heat treatment has been adopted in the large-scale locomotive manufacturing industry, greatly improving the life of the locomotive, mainly the laser heat treatment of the large crankshaft of the locomotive and the laser heat treatment of the locomotive diesel engine cylinder liner and the locomotive main reed. The manufacturing process of the mold is complicated, the precision is high, the shape is different, and the application is extensive, but the cost is often increased due to the short life of the mold, and the repair is difficult. The use of a laser to heat treat the surface of the mold has been gradually recognized and adopted, which can double the life of the mold without being limited by shape and size.
Laser-heat treated crankshafts have become more and more advantageous due to laser heat treatment, and various high-power CO2 laser heat treatment machines are constantly being introduced. Some large enterprises introduce advanced foreign equipment at any cost, such as Dalian locomotive and vehicle factory to introduce German 6000W CO2 laser for large crankshaft heat treatment production line. At the same time, the sales of domestically produced high-power CO2 laser heat treatment equipment have doubled every year, and laser heat treatment production lines have been developed in various places.
At present, the successful examples are the laser heat treatment production line for the crankshaft, cylinder liner and vertical reed of the locomotive of Dalian Locomotive and Rolling Stock Factory; the laser heat treatment production line of the diesel engine cylinder liner of Xi'an Internal Combustion Engine Factory; the laser heat treatment production line of the automobile engine cylinder liner of Beijing Internal Combustion Engine and Capital Automobile Company ; Changchun First Automobile Manufacturing Plant laser heat treatment production line. At the same time, laser processing centers of different scales have been established throughout the country to perform laser heat treatment for machine parts in various industries.
Laser is a high-tech, wide application field. There are three key technologies for laser heat treatment: high-power lasers; multi-degree-of-freedom processing equipment and matching with computers; laser heat treatment processes for different applications. After more than ten years of efforts by laser technicians in China, these three aspects have developed rapidly, creating conditions for the promotion of laser heat treatment technology. In recent years, the laser industry has grown at a double-digit rate, higher than the speed of the development of the international laser industry, and higher than the speed of industrial growth in the country. It shows that its prospects are ambitious.
The application of laser heat treatment technology is not widespread in China, mainly the application of laser technology, and there are different degrees of mystification and prejudice. Laser technology, laser heat treatment application promotion is not enough, lack of practice. Therefore, the scientific research results of laser technology, especially the laser heat treatment technology, should be oriented to the economy, market-oriented, and the whole society as soon as possible, mainly for industrial enterprises, and continue to promote and expand their applications.
In order to achieve this goal, it is important to establish a dedicated laser heat treatment production line. However, it is even more important to establish a multi-functional laser processing center to serve more small and medium-sized enterprises. In the United States, Europe and Japan, there are more than 800 such processing centers. Many cities in China have also established similar laser processing centers in recent years, serving all walks of life, playing a good demonstration role and creating Considerable economic and social benefits.
It is no exaggeration to say that laser heat treatment can solve almost all the problems of metal surface heat treatment, but the process must be continuously explored, explored and tested. Laser heat treatment centers can do this and develop their applications as quickly as possible. For example, in the ever-developing automotive and tractor repair industry, laser heat treatment has achieved very good results.
It can be predicted that the development and application of laser processing technology, especially laser heat treatment technology, will accelerate the process of laser industrialization in China.