Nonstationary formation of nanodispersed composites during vacuum deposition of a two-component vapor

Abstract

A model based on the Langmuir adsorption model and a program for numerical simulation of nucleation and condensation on a cooled substrate were developed to describe the nonstationary phenomena observed in experiments on the production of nanodispersed composites by vacuum deposition of a two-component vapor. Calculations performed for a mixture of silver and water vapor have shown that the nucleation processes of the condensed phases of the components mutually stimulate each other with silver nucleation playing a leading role. A number of unusual phenomena have been found: an increase in the relative rate of water vapor condensation with a decrease in its partial pressure; the absence of stationary condensation modes; the existence of a boundary regime that separates modes with increasing and decreasing silver concentration in the condensate; the formation of porous skeletons consisting of a condensate of one of the components filled with nanoparticles of the other component. The dispersion properties of the condensates for various condensation modes and the adhesion of the condensate to the substrate were determined.