Synthesis of a Nitridized Composite Material from Ferroalumosilicozirconium in the Combustion Regime
K. A. Bolgaru, A. A. Reger
Tomsk Scientific Center, Siberian Branch, Russian Academy of Sciences, Tomsk, Russia
Keywords: synthesis by combustion, SHS, nitridization, silicon nitride, aluminum nitride, zirconium nitride
Abstract
The possibility of obtaining a composite material from a ferroalloy based on silicon, aluminum, and zirconium nitrides by the method of self-propagating high-temperature synthesis is considered. It is shown that introduction of a nitrogen-containing additive on the basis of ferroalumosilicozirconium in amounts up to 35% to the initial ferroalloy leads to an increase in the nitrogen fraction, emission of the basic nitride phases in combustion products, deceleration of motion of the combustion wave front, and reduction of the maximum combustion temperature. It is found that introduction of a preliminary nitridized material in amounts of more than 20% makes it possible to convert combustion wave front propagation to a steady regime and to obtain combustion products with a macroscopically homogeneous composition. Under the conditions of natural filtration of nitrogen, combustion of a powder mixture based on ferroalumosilicozirconium and a nitridized material yields a composite consisting of AlN, Si3N4, ZrN, and α-Fe phases.
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