STRUCTURE AND PHASE FORMATION OF COMBUSTION PRODUCTS DURING Γ-ALON SYNTHESIS IN SHS GAS-STATTING MODE

Abstract

The paper studies synthesis of aluminum oxynitride (γ-AlON) under the conditions of SHS gas-statting at high pressures (10–100 MPa) of gaseous nitrogen including the mode of so-called conjoint combustion reactions (chemical furnaces). It was shown that chemical and phase compositions of combustion products, their structure and morphology of powder particles depend on the reagent ratio in the initial Al–Al 2 O 3 mixture, as well as nitrogen pressure, combustion temperature of high-exothermic components of chemical furnaces, and type of initial reagents. The structure of γ-AlON powder particles was studied and its relation to self-propagating high-temperature synthesis conditions was found. It determines the optimum SHS parameters for Al 5 O 6 N (γ-AlON) synthesis.