Thermal spraying technology has been widely promoted and applied in China. The development trend and characteristics in recent years are:
⑴Large area long-term protection technology has been widely used
For steel structures exposed to the outdoor atmosphere for a long time, the use of spraying aluminum, zinc and their alloy coatings instead of the traditional painting method, the implementation of cathodic protection for long-term atmospheric anti-corrosion, has developed rapidly in recent years. Such as large-scale projects such as TV towers, bridges, highway facilities, water gates, microwave towers, high-voltage transmission towers, underground cable supports, beacon buoys, shafts and shafts, spraying aluminum, zinc and their alloys are used for anti-corrosion. There are dozens of professional spraying factories in China engaged in this work, and the spraying area reaches more than several million square meters every year. This technology is not only widely popularized and applied in China, but also has been well promoted and applied in foreign aid projects.
⑵Repair and strengthen the localization of large equipment and imported parts
Repair and strengthen the localization of large equipment and imported parts. In recent years, there have been many successful application examples in this area, such as: one-meter-seven rolling mills, high-speed fan rotors, large extruder plungers, large gears, electrode extrusion forming nozzles, high-power Automobile crankshaft, etc. The progress of these works, firstly, to solve the urgent needs of production; secondly, to save a lot of foreign exchange.
(3) Application of supersonic flame spraying technology
With the development and improvement of China's thermal spraying technology, the requirements for the quality of the spray coating are getting higher and higher. In recent years, the high-speed gas (HVAF) method developed in the United States and other countries is a new process method for preparing high-quality coatings. Because the supersonic flame spraying method has many advantages, nearly a dozen sets of equipment have been imported from abroad in China, which play an important role in various industrial sectors.
⑷ Gas detonation spraying technology is further applied
This spraying technology is better than other spraying methods in some fields because the particle flying speed can reach more than 800m/s, the bonding strength between the coating and the substrate can reach more than 100MPa, and the porosity is less than 1%. More than 10 units have been installed in China.
⑸The rapid development of oxyacetylene flame plastic powder spraying technology
As mentioned above, in recent years, there have been many domestic manufacturers of oxyacetylene flame plastic powder spraying equipment. Using this technology, it has been used in chemical storage tanks, pipelines, clay machine plates and frames in the ceramic industry, and cloth guide rollers in the printing and dyeing industry. , Coal industry belt conveyor cast iron rollers, petroleum industry injection equipment, and surface decoration have been well applied, making up for the lack of EFI. It opens up a new way for the application of plastic coating.
⑹ Thermal spraying technology has been applied in chemical anti-corrosion engineering
Corrosion is one of the main reasons for the failure of mechanical components by the chemical or electrochemical action of the surrounding medium. It not only causes the loss of a large number of metal materials, but also the loss of production shutdown caused by it is more difficult to estimate, so people pay special attention to the chemical anti-corrosion work. Thermal spray coating used in corrosive media, especially strong media corrosion, has not been able to break through before, the main reason is that the sealing agent has not been solved. As we all know, there are pores in the spray coating. If the pore sealing treatment is not carried out, various acids, alkalis and organic media will penetrate into the pores, causing the coating to fall off and affecting the anti-corrosion effect. According to the requirements of anti-corrosion engineering, China has recently successfully developed dozens of types of sealing agents such as polyester type, organic polymer type, resin type, plastic type, adhesive type, etc., which are suitable for corrosion of acids, alkalis, salts and organic substances. Environment, its use temperature is 80 ~ 350 ℃. Using ceramic coating, oxide coating or metal or alloy coating, according to different media, choose appropriate sealing agent, which has been applied in many chemical corrosive media with good effect. This series of sealants has been patented and won the National Invention Award. The successful research of these sealing agents has made new progress in the application of thermal spraying technology in chemical anti-corrosion engineering.
⑺Laser remelting technology began to be applied
High-frequency induction remelting and vacuum induction remelting are only used in a certain range. Laser remelting technology has been tested on a small area in the past few years, but it has not been widely used. Recently, Tsinghua University has used laser remelting technology in valve production, and Shanghai No. 2 Textile Machinery Factory has applied laser remelting technology in textile machinery.
⑻ It has also been applied in the construction and decoration of medical and health
Thermal spraying technology has also been applied in building decoration, medical and health care. In recent years, Sichuan, Shanghai, Shenyang, Yunnan and other places have used thermal spraying technology to spray various statues, ornaments, large walls, etc., and have received good results. The large-scale mural of the peacock opening screen adopts thermal spraying technology. With the development and improvement of thermal spraying technology, this technology has penetrated into other fields, such as the use of thermal spraying in the biological field to manufacture artificial bones. There have been more than 200 clinical cases in China, and the effect is very good. In addition, artificial teeth manufactured by thermal spraying method have also been initially applied
