Effect of alloying on the kinetics and mechanism of oxidation of powdered aluminum-based alloys with rare- and alkaline-earth metals

The oxidation features of powdered metals associated with the presence of a barrier layer of reaction products on the particle surface is considered. It is shown that phase formation processes, the stresses resulting from an increase in film thickness during heating, and the thermal stresses on the oxide-metal interface lead to fracture of the protective layer, which affects the oxidation kinetics. A mechanism for the interaction of aluminum alloys with rare earth metals and Ca and Ba with air under programmed heating and the processes determining the reaction kinetics is proposed based on an analysis of their previously investigated physicochemical properties and experimental data on the oxidation of powders of these systems of various dispersity. The effect of particle size and alloying on the nature of the processes is studied.