METHOD OF PRODUCING COMPOSITE CERAMIC MATERIAL (VERSIONS) Russian patent published in 2010 - IPC C09K11/64 C04B35/10 

FIELD: chemistry.

SUBSTANCE: group of inventions relates to methods of producing luminescent composite ceramic material based on alpha-aluminium oxide and aluminium-magnesium spinel which can be used in making light-emitting and light signal devices, e.g. light-emitting diodes and traffic lights. In the first version the method is based on preparation of a composition by mixing powdered components which contain aluminium, magnesium and silicon, moulding the composition and then thermal treatment of the composition at temperature not exceeding 1650°C in an air atmosphere or in a vacuum. The method uses nanopowder components with particle size between 5 and 60 nm. The aluminium- and magnesium-containing component is taken in form of a solid solution of magnesium in aluminium oxide (Al_xMg_1-x)₂O₃ (1>x>0.6) in amount of 60-99 wt %, and the silicon-containing component is taken in form of silicon carbide SiC in amount of 1-40 wt %. The composition is moulded until attaining relative density of 0.3-0.9. Thermal treatment is carried out until the ceramic attains relative density of at least 0.6. The lower limit of the temperature range is equal to 1200°C, and the thermal treatment period ranges from 0.1 minutes to 200 hours.

EFFECT: obtaining composite ceramic material with an intense red colour emission in the 680-700 nm range.

48 cl, 12 ex, 1 tbl, 1 dwg