High Velocity Oxygen Fuel Spraying Coating
1,Three working mode:economic,Superior,Ultra
More uniform coating structure and high density(porosity less than0.2%)
Less or none decarb (undetectable by XRD)
Higher coating hardness(greater than 1600 HV0.3),less variations thru the coating areas(50-60HV vs.150-200 HV for conventional HVOF)
More wear resistant
Higher toughness and cavitation resistant properties
Gas tight with 50um thick WC coating under 200MPa nitrogen gas
Higher spray rate:5-10um/pass
Coating defect can be repaired locally.
It is an ideal choice for high temperature engineering materials. Due to the outstanding properties, Silicon Carbide Ceramic is also recognized as a mechanical sealing material better than metals, tungsten carbide, al2o3 ceramics etc. Moreover, it also has advantages of self-lubricating properties and low friction coefficient.
The tungsten carbide coating adopts HVOF sprayed cobalt-based tungsten carbide alloy powder or nickel-based tungsten carbide alloy powder and chromium-based tungsten carbide alloy powder. The hardness can reach HV1200 and high temperature resistance of 850 degrees, so that the valve parts are resistant to wear, corrosion and resistance high temperature, anti-oxidation. Exceeding manual surfacing, chromizing, carburizing, quenching and tempering, and process, the production efficiency can be increased by more than 2 times, the production cost can be reduced by more than 50%, and the service life can be extended by dozens of times.
Microstructure of tungsten carbide coating:
In the tungsten carbide coating, carbon atoms are embedded in the gaps of the tungsten metal lattice without destroying the original metal lattice, forming an interstitial solid solution, so it is also called an interstitial (or inserted) compound. Tungsten carbide can be made by heating a mixture of tungsten and carbon at high temperature. The presence of hydrogen or hydrocarbons can accelerate the reaction. If the oxygen-containing compound of tungsten is used for preparation, the product must be vacuum treated at 1500°C to remove the carbon and oxygen compounds. Tungsten carbide should be mechanically processed at high temperatures to make cutting tools, structural materials for kilns, jet engines, gas turbines, nozzles, etc.
✔Mechanial seal rings
✔Balls, seats, liners for valve
✔High Temperature kiln furniture
✔Fixed and moving turbine components
✔Components for burners
✔High strength in high tempperature
✔High-temperature oxidation resistance
✔Excellent wear resistance
✔Low thermal expansion and high thermal conductivity
✔Excellent thermal shock resistance
✔Outstanding corrosion resistance