WIRE FLAME SPRAY PROCESS
With the combustion wire spray process, the wire spray material is melted in a gaseous oxygen-fuel flame. The wire is fed continually into the fuel gas-oxygen flame, where it is melted and atomized by the addition of compressed air that also directs the melted onto the substrate.
Combustion wire spray is a common choice for machine element repair and corrosion coatings such as bridge piers and Yankee dryer Rolls. It’s possible to choose between hard (higher melt temperature) or soft (lower melt temperature) wires.
POWDER FLAME SPRAY PROCESS
The combustion powder process uses a similar technique of wire Flame spray process, except that the wire feed stock is replaces with powder. The process is basically the spraying of molten material onto a surface to provide a coating. Material in powder form is melted in a flame (oxy-acetylene or hydrogen most common) to form a fine spray. When the spray contacts the substrate, the fine molten droplets rapidly solidify forming a coating. This flame spray process carried out correctly is called a “cold process” (relative to the substrate material being coated) as the substrate temperature can be kept low during processing avoiding damage, metallurgical changes and distortion to the substrate material. The main advantage of powder flame spray process is that a much wider range of materials can be easily processed into powder form giving a larger choice of coatings.