Verfahren zur Herstellung von redispergierbaren hochreinen Nanospinellpulvern, redispergierbares hochreines Nanospinellpulver und daraus erzeugte dichtgesinterte transparente Spinellprodukte

DE 102009046036 A1 UPAB: 20110629 NOVELTY - The method for the production of dispersions stabilized, highly pure nanospinel powder with specific surface of 50-125 m2/g and ability for the production of highly-transparent sinter ceramics, comprises dissolving aluminum- and/or magnesium-containing basic materials that are hydrolyzed under stirring at 70-95 degrees C, ageing at 70-95 degrees C and then drying of the materials at 30-95 degrees C, calcinating the received powder at 1000-1100 degrees C and then carrying out a dispersion grinding in an organic fluid. Inorganic salt is used as aluminum- and magnesium-containing basic materials. DETAILED DESCRIPTION - The method for the production of dispersions stabilized, highly pure nanospinel powder with specific surface of 50-125 m2/g and ability for the production of highly-transparent sinter ceramics, comprises dissolving aluminum- and/or magnesium-containing basic materials that are hydrolyzed under stirring at 70-95 degrees C, ageing at 70-95 degrees C and then drying of the materials at 30-95 degrees C, calcinating the received powder at 1000-1100 degrees C and then carrying out a dispersion grinding in an organic fluid. Inorganic salt is used as aluminum- and magnesium-containing basic materials and is hydrolyzed together with a base. Metal organic precursor is used as aluminum and magnesium containing basic materials and is dissolved in organic, water-free solvent. The solution is hydrolyzed with water. Organic aluminum-precursor that is dissolved in organic water-free solvent is used as aluminum-containing basic materials, and/or magnesium oxide- or magnesium hydroxide-powder is suspended with a particle size of 0.3 mu m in the solution, or magnesium precursor that is dissolved in organic water-free solvent is used as magnesium-containing basic materials, and/or aluminum-oxide or aluminum hydroxide powder is suspended with a particle size of 0.3 mu m in the solution, where the suspension is hydrolyzed with water. Aluminum- and/or magnesium-containing germ with cubic crystal structure is used. The production of the solution or suspension and/or hydrolysis and/or ageing is carried out at 80-90 degrees C. Ammonia-solution or triethylamine is used as base for hydrolysis. Alcohol with chain length C greater than or equal to 2 is used as organic fluid for the dispersion grinding. The magnesium oxide- or magnesium hydroxide-powder or aluminum oxide- or aluminum hydroxide powder is used with a particle size of 25-150 nm. The suspension is added to dispersion additive. INDEPENDENT CLAIMS are included for: (1) a stabilized, highly pure nanospinel powder; and (2) a densely sintered, transparent spinel product. USE - Method for the production of dispersions stabilized, highly pure nanospinel powder useful for the production of highly-transparent sinter ceramics. ADVANTAGE - The method ensures efficient production of dispersions stabilized, highly pure nanospinel powder with high refractive index or thermal, chemical and mechanical resistance.