The Twin Wire Electric Arc 400 Process utilizes an arc spray head to melt the alloy feed wires. DC electric current is carried by two electrically conductive, consumable .0625 diameter wires, which are fed to the spray gun from a dual drive wire feeder. An electric arc forms between the wire tips in the gap where the two are continuously directed. A high velocity jet of nitrogen atomizes the molten metal as it forms continuously, while the wires are melted by the electric arc. The atomizing gas accelerates the fine metal droplets away from the electrode tips to the prepared substrate (base metal). The molten particles impact the substrate to form a coating in a series of thin (3-5 mil), overlapping layers to the desired thickness.