Detailed metallization spray process

Thermal spraying is used in a variety of coating processes, including plasma spraying, HVOF spraying, arc spraying and flame burning spraying. These processes are also known as metallization sprays.

Flame burning spray (particle speed range: 300-800 fps)

The fuel gas is burned with oxygen to melt continuously fed wires, powders or rods (temperatures up to 4600-5200°F). Compressed air is concentrated around the flame, atomizes the molten material into fine spherical particles, and pushes these particles at high speed onto the substrate.

Arc Spray (particle speed range: 500-1000 fps)

The two metal wires are charged with the opposite polarity and high voltage as the coating material. An inert gas (up to a temperature of 10,000-12,000°F) is injected to trigger the atomization of the material and push it towards the substrate to form a coating. This method requires a coating with a melting point below 10,000F.

Plasma Spray (particle speed range: 800-1800 fps)

Prior to the invention of the HVOF system, plasma guns were widely used to add speed to material particles. During the plasma spraying process, the material is introduced into the plasma jet and emitted from the plasma torch. It melts in the jet (up to 30,000°F), propels it toward the substrate and forms a coating. Almost any material with a melting point below 30,000F can be sprayed by this method.

HVOF spray (particle speed range: 2400-3200 fps)

High-velocity oxygen fuel (HVOF) is a method of pushing molten particles onto the working surface of each coating. The controlled combustion of fuel (liquid or gas) in an oxycombustion chamber produces high temperature combustion gases (up to 6,500F). The combustion process produces a rapidly expanding gas in the combustion chamber, resulting in a very high velocity gas.