Processing maps for reactive atomization and deposition processing

Abstract

A relatively new processing technique, Reactive Atomization and Deposition (RAD), has been developed to combine atomization, reaction and consolidation into a single step process in order to synthesize oxide, carbide, nitride, and other dispersion strengthened materials. Moreover, RAD processed materials exhibit enhanced thermal stability, relative to that of materials processed using inert gas, and that the thermal stability is improved with increasing oxygen concentration in the atomization gas, up to a maximum 35 wt.%. In order to realize in-situ, continuous control over the chemical reaction between the atomized droplets and the reactive atomization gas, it is necessary to define an inherent relationship among the oxygen concentration in the atomization gas, the amount of oxide particles formed and the influence of the reaction temperature. Therefore, it is the primary aim of the present study to provide fundamental insight into the effects of the processing parameters on the formation of oxide particles during RAD processing. An analytical model is developed to establish a quantitative relationship between the oxide film thickness and the oxygen concentration, including the effect of reaction temperature.