Home – Home – Jornals – Chemistry for Sustainable Development 2009 number 6

Macrokinetic characteristics of the combustion process in reaction mixtures Cr-B and Cr-Ti-B after preliminary mechanical activation were investigated. It was established that mechanical activation has a substantial effect on the composition and structure of the initial mixtures and therefore on temperature and rate of combustion of the mechanically activated mixtures. It was shown that the interaction between the reagents at the combustion temperature follows the solid-phase mechanism. The mechanisms of phase formation in the combustion wave were studied with the help of stopped-front method. With an increase in the concentration of oxygen in the mixture as a consequence of mechanical activation, the role of gas transport of boron to the surface of the metal increases; reaction diffusion becomes the limiting stage of the interaction of a metal with boron. It was established using X-ray structural analysis that the products of combustion of the mixture Cr-Ti-B contain previously unknown ternary compounds like Cr₄Ti₉B and Ti₂CrB₂.