Development of Optical Monitoring for Thermal Spray Processing

A new approach has been developed for monitoring thermal spray processing that involves visualization of the movement of particles using a high speed video camera and wide-band intensive illumination to measure particle temperature, velocity, size, and distribution. Synchronously with the capture of the particle parameters, the surface temperature of the coating is measured with a two-channel pyrometer that has high spatial and a temporal resolution. This paper presents the results of investigations of cold spraying and D-gun spraying using these techniques.