Flame wire spraying
Autogenous wire spraying or wire flame spraying is the oldest process in thermal spray technology. Using an electric or air motor a material is transported as a wire through a spray gun and melted down centrally in a burning gas-oxygen mixture (usually acetylene-oxygen). Subsequently, compressed air is used to spray the molten material onto the substrate to form a coating.
The extrudable materials for this process are metals and alloys that can be drawn into a wire shape, and have a melting point that is far below the temperature of the heat source used. If zinc, aluminium, or a zinc-aluminium alloy is used for the wires, it is also called metal spraying.
Material Form: Wire (sometimes cord or rod shape)
Thermal energy source: by combustion of a fuel and oxygen
Process fuel: propane, hydrogen, acetylene
Process temperature: < 4,000ºC
Spray particle speed: < 150 m/s
- Micro porous lamellar structure
- Relatively high degree of oxidation in the coating
- Moderate tensile strength
- Good compressive strength
- Low elongation properties
- Economic thermal spraying process
- Transportable process, coating on location possible
- Various stainless steel alloys
- Nickel-based alloys
- Copper and copper alloys
- Zinc, Tin, etc.
- Piston rings with molybdenum for improved wear resistance and running properties (coefficient of friction)
- Corrosion protection for locks, bridges, etc. with aluminium, zinc and their alloys
- Repairs or dimension corrections of worn drive shafts or bearing seatings with stainless steel alloys
- Sleeve bearing surfaces with white metal (Babbitt) or bronze
- Electrical shielding with tin, zinc, etc.