Particle size distribution in a wire-arc spraying system

The size and velocity of particles produced by a ValuArc 200 (Sulzer-Metco, Westbury, NY) twin-wire-arc spraying system were measured in-flight using a DPV-2000 system (Tecnar Ltd., St-Bruno, QC, Canada) for a range of operating parameters. A technique was developed to identify and separate the size distributions of particles produced by atomization of molten metal at either the anode or the cathode by assuming that both follow a log-normal distribution. It was shown that particles produced by the anode are almost two times larger in diameter than those originating from the cathode. Experiments showed that increasing the pressure of atomizing gas decreased the size of both anodic and cathodic particles, but changing wire feed rate and operating voltage did not change particle size significantly.