HVAF (High Velocity Air Fuel) thermal spray technology is similar to HVOF (High Velocity Oxy-Fuel) in that a fuel source is combusted to allow the propellant to accelerate the coating powder particles. However, HVAF diverges from HVOF in that it uses air as the oxygen source, eliminating the need for compressed bottle oxygen. The lower temperature burn of HVAF heats the sprayed powder particles less, thus controlling the thermal alteration of the coating. HVAF has the flexibility to generate HVOF-like coatings and coatings similar to those produced using cold spray. HVAF technology is well suited for tungsten carbide coatings on pump housings and axles for the oil and gas industries. HVAF is commonly used as a repair technology for the oil drilling and gas industries.
Advantages:
- Lower temperature than HVOF, resulting in less oxidation
- Compressive stress imparted to substrate surface
- High particle velocities (4000 ft/sec) for dense and well-bonded coatings
Applications:
- Aerospace dimensioning
- Chemical tank protection
- Oil refining and drilling
- Pulp and paper industries
- Maritime corrosion resistance
- Auto engine part repair
