METHOD FOR PRODUCING A NANOPOWDER OF YTTRIUM ALUMINIUM GARNET Russian patent published in 2021 - IPC B22F9/24 B82B3/00 B82Y40/00 C01F17/34 C04B35/44 

FIELD: chemical processes.

SUBSTANCE: invention relates to methods for producing powders of nanocrystalline yttrium-aluminium garnet, usable as an initial powder of oxide ceramics, in a dispersed state as a filler or pigment, or as an initial powder for producing a monocrystal or a coating applied by flame spraying, and can be applied in the laser manufacturing technology, in chemical and other branches of industry. The method for producing a nanopowder of yttrium-aluminium garnet includes preparation of initial solutions in the form of solutions of aluminium and yttrium nitrates, an ammonia solution as a precipitator, followed by mixing thereof using a microreactor, separation of the precipitate from the resulting colloidal solution and heat treatment thereof. The initial solutions of aluminium and yttrium nitrates and the ammonia solution are mixed using a microreactor with a central and tangential branch pipes for twisting the flows, wherein the initial solutions of aluminium and yttrium nitrates are supplied into one or several tangential branch pipes of the microreactor, and the ammonia solution is supplied into the other branch pipes of the microreactor, the amorphous precipitate is separated from the colloidal solution produced in the microreactor as a result of synthesis, filtered and subjected to heat treatment at a temperature of 1,100°C for 30 minutes resulting in a nanopowder of yttrium-aluminium garnet. The supply rate of the solutions into the branch pipes of the microreactor is no less than 4 m/s, and the flow rates of the initial solutions of aluminium and yttrium nitrates are set equal to ensure the stoichiometric ratio of yttrium and aluminium in the resulting yttrium-aluminium garnet.

EFFECT: synthesis temperature is reduced, homogeneity of the resulting powder is increased, and degree of particle agglomeration is decreased.

1 cl, 4 dwg, 1 tbl