Abstract
The processing of metallic alloys with the atmospheric HVOF process requires a uniform setting of the particle parameters, particle temperature and velocity, as these determine the tendency towards oxidation and the flattening behavior of the particles. Using the example of a NiCr alloy, this paper examines the effects of different particle diameters of a typical HVOF grain fraction on the achievable uniformity of processing. In addition, particle parameters are correlated with the process variables fuel gas composition and spray distance as well as the resulting application efficiency in order to determine whether they can be influenced. The particle properties of surface temperature and speed are characterized with the aid of a high-speed particle pyrometer. It is shown how, with the help of this particle diagnosis, an on-line process control can be used as proof of quality assurance. Paper includes a German-language abstract.
