Application of Thermal Spray Tungsten Carbide Ceramic Coating in Metal Wire Making Equipment such as Pulley of Wire Drawing Machine

       Ceramics with carbon-containing refractory compounds as the main component. It can be divided into two categories: metalloid carbides (such as titanium carbide, zirconium carbide, tungsten carbide, etc.) and non-metallic carbides (such as carbon tetraboride, silicon carbide, etc.). Carbide is a high temperature resistant material.



Many of the carbides have softening points above 3000°C. Most carbides are more resistant to oxidation than carbon and graphite. Many carbides have high hardness and good chemical stability.



There are four methods for preparing metalloid carbides: (1) After mixing metal oxides and carbon black, they are prepared by heating to 2000-2500 ° C in a graphite tubular resistance furnace or vacuum electric furnace; (2) Metal and carbon are prepared in hydrogen , carbon monoxide or methane and other protective atmosphere at 1200 ~ 2000 ℃ high temperature synthesis; (3) with carbon-containing gas metal carbide (or its oxide) synthesis; (4) metal halide, carbon monoxide and carbon or hydrogen synthesis The gas mixture interacts to obtain vapor-deposited carbides.



General products can use conventional molding methods. For products with complex shapes, slurry casting method and injection molding method can be used. They have a covalent bond structure and are difficult to sinter. Atmospheric pressure sintering method, reaction sintering method, hot pressing sintering method, impregnation method and recrystallization method are mostly used. Carbide ceramics are widely used as heat-resistant materials and superhard tools.



Spraying process method:



1. Supersonic flame spraying method: hvof (high velocity oxy-fuel) supersonic flame spraying is a high-speed flame spraying method that can form dense coatings at high speed.



Supersonic flame spraying is to mix gaseous or liquid fuel with high-pressure oxygen and burn it in a specific combustion chamber or nozzle. The resulting high temperature and high-speed combustion flame are used as the heat source, and the powder material or wire is sent to the center of the flame jet. It is melted or semi-melted, and then the thermal spraying method of high-speed continuous spraying is carried out.



Because the powder coating material hits the substrate at supersonic speed, it can form an extremely dense, high-bonding coating. It is of real value especially in the formation of wear resistant coatings of carbide cermet materials.



The speed of the burning flame is several times the speed of sound, and the bright "Mach Festival" in the flame can be seen visually, so hvof is generally called supersonic flame spraying.



Supersonic flame spraying was successfully developed in the 1980s. Different from conventional flame spraying, supersonic flame spraying uses a specially designed combustion chamber and nozzle to drive a large flow of fuel and use high-pressure oxygen to support combustion, thereby obtaining extremely high speed. combustion flame. A spray gun using liquid fuel, also known as high pressure hypersonic flame spray (hp-hvof)



1. New and strengthened repair of godet roller and wire drawing steel ring by supersonic spraying;



2. Enamelling machines, stainless steel wire drawing, winding machines, tinning machines, copper wire drawing machines and other equipment; new and repaired drums, wire wheels, etc.;



3. New and repair of large, medium and small wire machine tower wheel and guide wheel, wire drawing tower wheel, wire drawing wheel, wire wheel, wire drawing cylinder, wire take-up reel, guide groove, wire drawing kettle, etc.