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Background: High purity nanosized aluminum nitride synthesis is a current issue for both industry and science. However, there is no up-to-date review considering the major issues and the technical solutions for different methods. This review aims to investigate the advanced methods of aluminum nitride synthesis and its development tendencies. Also the aluminum nitride application patents and prospects for development of the branch have been considered. Methods: The patent search on “aluminum nitride synthesis” has been carried out. The research activity has been analyzed. Special attention has been paid to the patenting geography and the leading researchers in aluminum nitride synthesis. Results: Aluminum nitride synthesis methods have been divided into 6 main groups, the most studied approaches are carbothermal reduction (88 patents) and direct nitridation (107 patents). The current issues for each group have been analyzed; the main trends are purification of the final product and nanopowder synthesis. The leading researchers in aluminum nitride synthesis have represented 5 countries, namely: Japan, China, Russia, South Korea and USA. The main aluminum nitride application spheres are electronics (59,1 percent of applications) and new materials manufacturing (30,9 percent). Conclusion: The review deals with the state of the art data in nanosized aluminum nitride synthesis, the major issues and the technical solutions for different synthesis methods. It gives a full understanding of the development tendencies and of the current leaders in the sphere.

The microstructure of SiC matrix composite materials produced by pressureless aluminum melt infiltration at 950° was investigated. The oxygen containing phases fraction in silicon carbide preform does not considerably change after soaking in molten aluminum due to the formation of a dense flux film at the surface. It is established that during the direct infiltration of aluminum from the melt into sintered SiC preform, several areas are observed: aluminum saturated zone, transition zone, and a porous silicon carbide zone. The depth of the first area is 1.0–1.2 mm. The open porosity of the infiltrated composite material significantly improved from 8.5% for a SiC preform to 2.4% as well as density increased from 2.17 to 2.85 g/cm3. Even aluminum content in the zone of porous silicon carbide has grown 5.5 times. The corundum phase has formed at the composite material surface within cooling in the air atmosphere. The hardness distribution over the specimen depth has a parabola-like appearance with a clear maximum on the surface (5.9± 0.6 GPa) and an obvious minimum coinciding in value with the hardness of the initial preform in the geometric center of the sample (2.5± 0.3 GPa). The developed silicon based composite material could be considered as a prospective wear resistant lining.