The closer you come to the specific industry, the more you are going to see this regularly applied acronym. HVOF is an easy to memorize acronym for the use of high velocity oxygen fuel. It is generally utilized in a spray carrying oxygen fuel and leads to the formation of protective coating materials. Alternative to the hvof coating process will be the administration of a plasma spray with an electric arc included. HVOF coating and plasma spraying achieve similar objectives.
Both applications are made in accordance with AS 9100 standards. The plasma spray utilizes a high transfer of heat from a high KW electric arc. This is done through a plasma forming gas. The gas is directed through flow enhancing nozzles. When heat as high as 10,000 degrees Fahrenheit is achieved, ceramic or metallic powder can be injected through an exit plume. The materials are plasticized in hot gas and transferred to its targeted surface at a high velocity.
HVOF coating materials go through a gun that uses nitrogen as its carrier gas. In this process, fuel gas meets oxygen through a siphoning system in the front of the gun. Gases are then ejected from the gun’s nozzle and ignited externally. The ignited gases form circular flame configurations that surround the powdered spray material while it exits the gun and is transferred to its targeted surface.
The two processes outlined here can be referred to another widely used acronym; PTA. PTA refers to the plasma transfer arc. This method deposits superior quality powders with low dilution rates to surfaces. In this transfer process, metallurgically fused deposits are formed onto a metal surface. And there is yet another deposit to surface process. It is known as the twin wire arc spray.