Tungsten carbide spraying is mainly used in ceramic coatings, and currently provides comprehensive protection solutions that integrate protective coatings, personalized protection scheme design, and engineering and technical services for power, steel, and cement companies. Now the remanufacturing industry has been classified as a national emerging strategic industry. Thermal spraying technology has a wide range of spraying materials, unlimited substrate shape and size, easy control of coating thickness, simple process operation, low cost and high efficiency, and can give parts with special surfaces. Performance and other characteristics are the key technical means to achieve surface size recovery and performance improvement of damaged parts. It has been successfully used in the remanufacturing of equipment parts and components in the fields of defense industry, printing, aerospace, petrochemicals, mining machinery, power and other fields. Including various shafts, pump valves, sealing rings, sputtering targets, corrugated rollers, various valves, rolls, fan impellers, drawing tower wheels and other high wear-resistant products and other components and components Thermal spraying of corrosion, conductivity, insulation and other coatings.
Remanufacturing of plasma spray technology.
Plasma spraying technology began in the late 1950s. It is a process method that uses plasma arc to heat and accelerate spraying materials to finally form a coating. It is the process with the highest heat source temperature and the most concentrated energy in thermal spraying technology. The characteristics of high temperature and fast jet velocity can theoretically spray all materials with physical melting point.
a. Remanufacturing thin-walled parts for heavy-duty tracked vehicles
In the 1970s and 1980s, Xu Binshi led the team members to apply ordinary plasma spraying technology for the first time in China to repair thin-walled parts of heavy-duty tracked vehicles. Nickel-clad aluminum was used as the base material for spray coating. Mainly, the repairing and strengthening of the inner circle sealing ring mating surface in the compression wheel and the inner circle self-pressure oil stop mating surface of the wrap-around oil cap are mainly strengthened. Academician Xu Binshi put forward the concept of "strengthening repair", that is, scrapped parts were treated with plasma spraying, which not only restored the size but also prolonged the service life. This technical idea laid the technical foundation for the reform of the maintenance system of heavy-duty tracked vehicles.
b. Remanufacturing of piston skirts for heavy-duty vehicle engines
The piston skirt is an important part of the piston group. It mainly plays the role of guiding and heat transfer, and it can withstand the lateral thrust from the crank and linkage mechanism. During the use of the aluminum alloy piston, due to the abnormal cooperation of the piston and the cylinder liner, the piston skirt is scratched and worn, which affects the life of the cylinder liner. Aiming at the working conditions and wear patterns of the piston, and considering the material of the substrate, Wang Haijun et al. Used the supersonic plasma spray AlSi + Ni / Al composite coating to repair and strengthen the piston skirt.
c. Remanufacturing of anilox rollers for printing machinery
Engraved anilox rolls are commonly used on flexographic, gravure, high-quality coating and laminating machinery. To meet the requirements of high abrasion resistance on the surface of the anilox roller, plasma sprayed ceramic coating can be used to repair the traditional chrome-plated failure roller, and then laser engraving to make the ceramic anilox roller. After remanufactured by plasma spraying technology, the ceramic anilox roller has high hardness (1100 ～ 1300HV), and has greatly improved the abrasion resistance, corrosion resistance and hydrophilic properties. The printed image is clear and realistic.
d. Remanufacturing of high temperature components for aerospace engines
With the continuous development and performance improvement of aero engine technology, the operating temperature of the engine has gradually increased. At present, the outlet temperature of the compressor of the advanced engine has reached 650 ° C, the working temperature of the combustion chamber and the afterburning chamber is close to 2000 ° C, and the inlet temperature of the turbine has reached 1650 to 1750 ° C. The parts of these parts are mostly made of titanium alloy, nickel alloy and other materials. The temperature they endure is limited and they often fail due to high temperature fatigue. Studies have shown that it is difficult to make breakthroughs in increasing the operating temperature of parts by adjusting the base material. Thermal barrier coating is a mature and enhanced repair technology applied in the aerospace and aerospace fields. It adopts plasma spraying technology to prepare oxide ceramic coatings on the surface of high-temperature alloy substrates, and realizes aviation through the thermal insulation effect of ceramic coatings. 2. The use temperature (temperature resistance) of the hot-end parts of the space engine is improved.