METHOD OF PRODUCING DENSE NANOCERAMICS BASED ON ALUMINUM OXIDE IN THE AlO-ZrO(YO) SYSTEM Russian patent published in 2019 - IPC C04B35/119 C04B35/626 B82Y30/00 

FIELD: manufacturing technology.

SUBSTANCE: invention relates to the technology of producing composite nanoceramics with high microhardness and bending strength, which can be widely used in various fields of modern technology. Method is characterized by that aqueous solutions of salts of Al(NO₃)₃, ZrO(NO₃)₂ and Y(NO₃)₃ poured into NH₄OH, and obtained gel-like precipitates are washed with distilled water and filtered by water-jet pump, then aluminum hydroxide precipitate is heated to temperature of 300 °C and held until formation of boehmite phase AlOOH, and gel-like precipitate of zirconium and yttrium hydroxides is fired at 400 °C to obtain metastable solid solution based on (c'-ZrO₂) with pseudo-cubic structure. Powders-precursors AlOOH and c'-ZrO₂ mixing in given ratio, powder mixtures in Al₂O₃-ZrO₂(Y₂O₃) system is subjected to mechanochemical activation in a planetary mill with grinding balls from high-density aluminum oxide ceramics in dry grinding mode, while observing the ratio of the mass of grinding balls to the total weight of powders of 1.0:1 and duration of mechanochemical activation from 5 to 40 minutes. Products are pressed from mechanically activated mixtures of precursor powders and sintered at temperature range of 1,400–1,500 °C. In optimal mode of consolidation (P_press.=200 MPa and 1,400 °C) mechanically activated powders are used to obtain composite nanoceramics with porosity of 1.5–2.5 %, microhardness of 18–19 GPa and bending strength of 680–720 MPa.

EFFECT: disclosed is a method of producing dense nanoceramics based on aluminum oxide in the Al₂O₃-ZrO₂(Y₂O₃) system.

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