An electric arc spray gun is a type of thermal spray gun that uses an electric arc to melt and atomize wire feedstock, which is then deposited onto a substrate to form a coating. The wire is fed into an electric arc generated between two electrodes, which melts and atomizes the wire into fine droplets. The droplets are propelled towards the substrate by the high velocity of compressed air or gas, and impact onto the surface, forming a coating.
Electric arc spraying is a thermal spraying procedure that utilizes an electric arc as the heat source between two consumable electrodes of the surface materials. A compressed gas atomizes the molten material and drives it to the workpiece. The figure depicts the process's basic principles. A wire feeder feeds the two consumable electrode wires, bringing them together at an angle of around 30 degrees and maintaining an arc between them. A compressed air jet is situated just behind and in line with the intersecting wires. The wires melt in the arc, and the air jet atomizes the molten metal, propelling the fine molten particles to the workpiece. A direct-current constant-voltage welding machine is used to generate the arc. Except that it feeds two wires, the wire feeder is similar to that used for gas metal arc welding. The gun can be held in one's hand or attached to a holding and moving mechanism. To provide a coating surface on the part, either the part or the gun is moved relative to the other.
The high arc temperature melts the electrode wire faster and deposits particles with higher heat content and fluidity than the flame spray gun procedure. Deposition rates are three to five times higher, and binding strength is 5000-7000 PSI. In addition to the mechanical link, there occurs coalescence. When compared to flame spraying, the deposit is denser and the coating strength is higher.
Electric Arc Spray Process
The parameters of the electric arc spray gun process can be simply modified to provide a variety of surface profiles. When rough surfaces are required, the coating settings are changed to provide coarse atomization of the melting wires. By feeding two separate wires, you can construct unique chemistries.
To replace badly worn equipment, electric arc coatings can generate relatively thick coatings. They are also easily machined to print specs and have many times the wear resistance of the original component substrate.
Electric arc spray guns offer the advantage of being able to produce coatings with high deposition rates and high bond strength, making them suitable for heavy-duty applications. They also require relatively simple equipment compared to other thermal spray processes. However, they may require more frequent maintenance due to the high temperatures and electrical currents involved in the process.
Electric arc spray guns are commonly used for surface coatings in various industries, such as aerospace, automotive, and marine, as well as for repair and maintenance applications. They can be used with a variety of materials, including metals and alloys, and can produce coatings with a range of thicknesses and properties.
Electric Arc Wire Spray Gun Advantages
Electric arc spray coatings can offer the effects you need, whether you need a smooth, rough, thin, or thick covering. Arc spraying is easy to use and produces very consistent, controlled surface outcomes. Among the advantages of using an electric arc spray are:
- Resistant to a wide range of corrosive conditions.
- Coatings that are galvanically active and sacrificial.
- Wear, erosion, and cavitation resistance.
- Resistance to oxidation at high temperatures.
- Biofouling materials should be avoided.
- Dimensional reconstruction.
- Surface profiles that can be controlled or textured.
- Surfaces that grip and are anti-skid.
Overall, electric arc spray guns offer a cost-effective and versatile solution for a variety of coating applications, particularly for applications that require high deposition rates and high bond strength.