Kinetic Metallization (KM) is an emerging technique for applying metallic and metal-matrix coatings to metallic, ceramic, and polymeric surfaces.  This impact consolidation technique provides significant benefits over many other coating technologies which include low temperature (minimizes thermal degradation of the coating or substrate), environmental compliance, and requires no masking.  Kinetic Metallization uses friction compensated sonic nozzles that are optimized for accelerating powder particles to velocities sufficient for applying coatings at low operating pressures.  Low operating pressures equate to decreased gas consumption, leading to low operating cost.  Particles acceleration, via drag force, is inversely proportional to powder particle mass.  Therefore, KM requires particle sizes with a maximum upper limit.  High quality, low porosity, high deposition efficiency KM coatings are produced with powders of a specific particle size and particle size distribution. This presentation will focus on the relationship between particle size and the velocities required for impact consolidation of powders.  In addition, the influence of particle size distribution on the quality of the coatings in terms of density and purity will be presented.