METHOD OF OBTAINING TRANSPARENT CERAMICS OF YTTRIUM-ALUMINUM GARNET

摘要

FIELD: nanotechnologies.;SUBSTANCE: invention relates to nanotechnologies and specifically to methods of producing novel transparent consolidated functional materials (ceramics) with high mechanical characteristics for photonics and laser equipment. Method of obtaining transparent ceramics of yttrium-aluminum garnet (YAG) involves obtaining nanopowder of YAG with its drying and subsequent spark plasma sintering at external pressure, wherein by combined high-energy grinding in ethanol of initial powders of oxides Y₂O₃, Nd₂O₃ and Al₂O₃ forming weakly aggregated YAG stoichiometry powder system with ratio of average particle sizes Y₂O₃, Nd₂O₃:Al₂O₃ 1:2.5–1:6 in range of 50–500 nm, drying is performed at temperature of 60–80 °C for 24–48 hours with subsequent granulation of powder through a sieve with effective mesh size of 75 mcm and subsequent annealing in air atmosphere at 600–800 °C for 2–4 hours, after which obtained material is heated at external pressure of 30 MPa at rate of 100 °C/min up to 1,000 °C, and then at rate of 30 °C/min up to 1,350 °C and maintained at this temperature and pressure of 5–10 minutes, further, obtained sample is annealed in air atmosphere for 1 hour at 900 °C heating and cooling rate – 200 °C/h and 400 °C/h, respectively. YAG stoichiometry powder system annealing is performed at heating and cooling rate 2.5 °C/min.;EFFECT: invention enables to obtain a monophase transparent ceramics YAG:Nd (≤ 4 at%), having an average grain size of 500–700 nm, microhardness 14–15 GPa and coefficient of linear optical transmission 70–75 % in visible wavelength range.;1 cl, 2 dwg, 1 tbl