POLYCRRYSTALLINE MATERIAL, METHOD FOR THE PRODUCTION THEREOF AND ARTICLES MADE THEREFROM

摘要

1. Polycrystalline material comprising crystallites of partially stabilized zirconium dioxide, wherein said crystallites are needle or lamellar-shaped having dimensions not exceeding 0.05 mm, with ratio of the length to maximum cross-section being not less than 2:1 which are oriented parallel to larger axes thereof and forming a rectangular grid. 2. Material according to claim 1, wherein comprising metal oxide selected from the group of ytterbium, cerium, calcium and magnesium oxides as stabilizing oxide. 3. Material according to claim 1, wherein further comprising metal-chromophore oxide selected from the group of transitional and/or rare-earth elements. 4. Material according to one of claims 1 to 3, wherein metal-chromophore oxide amounts to 5 mol%. 5. Material according to claim 1 or 2, wherein it is of black color resulted after heat treatment at 1650-1750 degree C during at least 3 hours. 6. A method for producing material comprising loading charge of zirconium dioxide and stabilizing oxide into a being cooled container, its melting forming a melt, subsequent crystallization by horizontal displacement thereof relative to an inductor at a rate of 0.1-30 mm/hr, cooling the container to 1300-1400 degree C, wherein the process is carried out with horizontal displacement thereof relative to an inductor, prior to crystallization the melt is maintained for at least 3 hours, the crystallization and the container cooling to 1300-1400 degree C are performed at reduced pressure of 200-300 mm of mercury column and cooling below 1400 degree C is carried out at a gradual pressure rise during at least 24 hours. 7. The method according to claim 6, wherein zirconium dioxide is used in the form of powder and/or crystalline wastes. 8. The method according to claim 6, wherein metal oxide selected from the group of ytterbium, cerium, calcium and magnesium oxides is added into the charge as stabilizing oxide. 9. The method according to claim 6, wherein after reducing the container temperature to 1300-1400 degree C, melting is repeated at a rate not exceeding 100 mm/hr. 10. The method according to claim 6, wherein the obtained material is subjected to annealing at 600 to 1400 degree C at atmospheric pressure or at 1100-2000 degree C at a pressure not less than 10<-1> mm of mercury column during 1-20 hours. 11. A tool based on partially-stabilized zirconium dioxide, wherein the material having the structure of claim 1 is used as the partially-stabilized zirconium dioxide.