Abstract
Nozzle geometry, which influences gas dynamics and, therefore, sprayed particle behavior, is one of the most important parameters in cold spray process. The gas flows in the entrance convergent section of the nozzle exhibit a relatively higher temperature and are subsonic; thus; this region is most suitable for heating spray particles. In this study, numerical simulation and experiments investigated the effect of the nozzle contour (convergent-divergent and convergent-divergent-barrel) and entrance geometry of convergent-divergent nozzle on the cold spray process. The process changes inside the nozzle, as obtained by numerical simulation studies, were related to the coating properties. A copper powder was used for the experimental studies. Working gas (is nitrogen) pressure and temperature at nozzle-intake were 3MPa and 573K. The change in the nozzle contour and entrance convergent section length of the gun nozzle had a significant effect on the particle deposition.
