Abstract
The technique was examined to prevent errors during thermal spraying by setting up a spray on-line monitoring system (Spray Watch-2i System) at the starting position in the production line using plasma spraying, and monitoring the characteristics of the particles in the plasma flame between each spraying cycle. The tests were carried out with several spray conditions, changing the gas flow, and the arc current. The state of the plasma flame was measured as the velocity, temperature and flux density of the flying particles. The coating properties were then evaluated by measuring the dielectric breakdown test. It has been found that the evaluation result of the coating correlates very well with the monitoring results of the flame particle characteristics. Therefore there is a possibility that monitoring the state of the particle characteristics within the flame during spraying can control the coating characteristics comparatively easily.
