This process differs from other thermal spray processes in that there are no
external heat sources as in any the combustion gas/flame spray processes.
Heating and melting occur when two electrically opposed charged wires,
comprising the spray material, are fed together in such a manner that a
controlled arc occurs at their intersection. The molten metal is atomized and
propelled onto the prepared workpiece by jets of compressed air or gas.
Typically, power settings of about 450 A can spray over 50 kg/hr (110 lb/hr).
Electric arc spray systems are offered that feed wire by either an air or
electrical motor. Some units push the wire to the gun while others pull the wire
into the arc. Controls include volt and ampere meters and air regulators.
1. Insulated housing for contact
piece; 2. Contact piece; 3. Heat resistant
protective plate; 4. Wire guides; 5. Atomizing air nozzle; 6. Arc point; 7.
Metal particles; 8. Atomizing air stream.