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Results of a study of the products of burning mixtures of titania and zirconia with aluminum nanopowder in air are described. It is shown that when these mixtures burn in air the TiN and ZrN phases are stabilized. According to the data of x-ray diffraction phase analysis the materials contain 55% ZrN and 24% TiN. It is most probable that the TiN and ZrN form through formation of element metals.The recent state of science and technology requires creation of new materials capable of withstanding high temperatures and operating in chemically aggressive media. Among the ceramic materials much attention is attracted today to nitrides of groups III and IV of the Periodic System. It is known that ceramics based on aluminum nitride possess high thermal conductivity [280 W/(m·K)], which is comparable to that of metallic silver. At the same time, AlN is a good dielectric (< 10 13 W·m), has a high enough hardness (12 GPa), and is nonwettable by liquid metals (aluminum, gallium, etc.). Zirconium nitride is a material with high hardness and resistance to alkalis. Coatings from titanium nitride possess an elevated wear resistance. Due to their peculiar properties ceramics and coatings based in titanium and zirconium nitrides present interest for engineering and various technologies.The known commercial methods for obtaining titanium and zirconium nitrides, including that of self-propagating high-temperature synthesis (SHS), have some disadvantages, i.e., require intricate equipment and occur under pressure in the presence of pure nitrogen. SHS products are densely sintered materials and are therefore disintegrated in ball mills, which is a high-energy-consuming process.A scientific direction known as "chemical bonding of air nitrogen due to combustion of powder materials and boron" has been developed at the High-Voltage Research Institute of the Tomsk Polytechnic University and is used as a method for fabricating ceramic nitride-containing materials (the combustion products contain over 50 mass % various nitrides [1]).Synthesis of nitride-containing ceramic powders due to burning of metal powders in air [2] has some advantages over commercial methods and SHS, i.e., lower consumption of energy, no necessity for intricate equipment, and presence of gradually varying layers between different crystalline phases. Combustion of nanopowders yields up to 90% products with submicron sizes [3].It is known that aluminum, titanium, and zirconium exhibit reducing properties at high temperatures [4]. For example, in combustion of aluminum thermit (Fe 2 O 3 + Al) aluminum reduces iron oxide (III) to metallic iron. The reducing capacity of powdered aluminum in combustion has also been studied for Cr 2 O 3 , WO 3 , MoO 3 , NiO, and CoO mixtures with aluminum. The use of titanium and zirconium powders at the commercial scale is fraught with a danger of their inflammation [5]. In addition, titanium and zirconium powders are less expensive products than their oxides. We have no published data on the products of combustion of zirconia mixtures wit...

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It is experimentally found that intermediate products of combustion of mixtures of aluminum and tungsten nanopowders in air are aluminum nitrides, remainders of metallic tungsten and aluminum, complex oxides, and possibly tungsten nitrides. These products were obtained by terminating the combustion process when a temperature close to the maximum value is reached.

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