HVOF is same in theory to combustion flame spraying, but it uses a different torch design that enables the flame to expand when the spray nozzle is activated. This causes a surge in acceleration, which in turn accelerates the mixture particles. When the mixture is released from the nozzle, the velocity of the mixture leads to a very thin and evenly applied coat. The final coating is well adhered, strong, and dense. Its hardness, corrosion resistance, and overall wear resistance is superior to plasma spraying. Because of the low temperature of the torch flame, which both melts the powder and propels the coating’s deposition, the mixture is not suited to withstanding high temperatures.
HVOF Thermal Spray Coating benefits are:
- Reduced oxide content
- Reduced solutioning of carbides
- Neutral or compressive stress
- Smoother sprayed surface
- True coating uniformity
- Tensile band strength >10,000 psi