Plasma Spraying with Low Power Consumption and High Efficiency

An innovative plasma spraying technology has been developed with low power consumption and high deposition efficiency. The plasma torch was operated at arc currents from 50 to 150A and voltages from 50 to 80V. The powder particles were injected into the arc region from the inside of nozzle entry by the carrier gas that then transferring through the plasma flame. The ceramic coatings of Cr₂O₃ and ZrO₂- Y₂O₃ were created at power consumption less than 10kW and powder feed rate of 30-50g/min. The deposition efficiency could reach 70%, higher than that of 40kW APS with an external powder feed. In addition, the enthalpy, temperature and velocity of low power plasma jet were also measured by an enthalpy probe.