Effects of the atomizing gas with three different
nozzle configurations on the porosity of the coatings
are shown in Fig. 10. The porosity of the coating is
related to the impact velocity of the droplets as well
as the droplet size. Air, as an atomizing gas, leads to
coatings with higher porosity because larger droplets
are produced as shown in Fig. 8. The c-d nozzle
produces coatings with lower porosity when compared
to the standard nozzle because of the higher velocity
of the atomizing gas. The nozzle with the HV cap
produces coatings with the lowest porosity, because
the HV cap produces a high level of turbulence
w x resulting in small droplets 2 .