Electric arc metal spraying

摘要

Method of thermally depositing metal at increased rates onto a target surface, comprising: establishing and operating a high velocity plasma transferred wire arc between a cathode and the free-end of a consumable wire electrode, the energy of such plasma and arc being sufficient to not only melt and atomize the free-end of the wire into metal particles, but also project the particles as a column onto the target surface at an enhanced deposition rate for continuous periods in excess of 50 hours; surrounding the plasma and arc with high velocity and high flow gas streams that converge beyond the intersection of the wire free-end with the plasma-arc to limit turbulence of the plasma-arc, avoid direct impingement with the wire and assist the projection of the particles to the target surface; and impinging a low velocity gas flow along the axis of the advancing wire to counteract any destabilizing fluid dynamic forces attempting to move melted particles back along the wire away from the wire free end.