High pressure and flows of oxygen and air craft grade fuel gas are ignited and create a high velocity stream. Powder material is injected in the high velocity stream where the material is only partially melted then propels at a high velocity to the prepared work surface. Upon impact, through kinetic energy, the material is then fully melted forming a coating. HVOF coatings are applied in compression instead of containing residual stress. This provides the best wear resistance.
Energy Source & Consumption | Oxygen & Fuel Gas, 700 to 2500 Scfh | |
Spraying Factors | ||
| Spray Rates | 5 to 15 lbs/hour | |
| Deposit Efficiencies | 30% to 50% | |
| Deposit Per Pass | .0005” to .001” | |
| Particle Velocities | 3500 to 3900 fps | |
Coating Properties | ||
| Materials | Tungsten Carbide, Chromium Carbide | |
| Coating Finishing Processes | Grind | |
| Hardness Range of Materials/Coatings | Rc 65-78 | |
| Typical Oxide Content | Less Than 1% | |
| Typical Porosity Levels | Less Than 1% | |
| Erosion Resistance Rating | Excellent | |
| Abrasive Wear Resistance Rating | Excellent | |
| Thermal Cycling & Thermal Shock Capabilities | Fair | |
| Co-efficient of Thermal Expansion & Contraction | Fair to Excellent | |
| Corrosion/Oxidation Resistance Rating | Good | |