Doped Crystalline Corundum
Doped Fine Crystalline Corundum
Tech Area / Field
- MAT-SYN/Materials Synthesis and Processing/Materials
8 Project completed
Senior Project Manager
Alexandrov K A
Institute of General and Inorganic Chemistry (IONKh), Russia, Moscow
- Moscow State University / Department of Chemistry, Russia, Moscow
- SAWYER Research Products, Inc., USA, OH, Eastlake
Project summaryThe main aim of the project is to develop a new technology of doped fine crystalline corundum and the use of this technology for reorientation of the industry specialized on the materials for military equipment. Earlier authors of the project showed that heating of aluminium hydroxide Al(OH)3 in water vapour atmosphere leads to its consequent transformation into boehmite (AlOOH) and then to corundum (a-Al2O3). Impurities ions easily penetrate into the boehmite structure on the stage of its formation and then became incorporated into the structure of corundum crystals. Such method of introduction of doping ions into crystalline corundum in the course of its synthesis allows to dope corundum by different elements at relatively low temperature and pressure (T = 380-420 °C, P = 100-260 atm). Corundum synthesized by this method represents fine (1-300 mm) well edged crystals with homogeneously distributed doping element.
Preliminary studies finished up to now show that doping of corundum by specific elements results in increasing of its abrasive properties and mechanical strength. Moreover luminophores with intensive luminescence in visible range of spectrum were obtained by doping corundum according this method.
Studies were performed by the group of scientists of IGIC RAS and Chemistry Department of MSU using scientific equipment of these research centres and of JSC “The Quartz Glass Plant”. At present the main problem is to fundamentally investigate the mechanism of doping elements incorporation into the structure of corundum in supercritical water vapour and to elucidate the dependence of doped corundum properties of the nature of doping element.
Obtained results will allow to predict optimal conditions of synthesis and to control properties of doped corundum.
Additional modification of synthesis technology will be carried out using pilot facility of IGIC RAS after finishing the laboratory studies and determining optimal conditions of synthesis of doped corundum with high abrasive and luminescent properties.
The development of technological regiments of doped fine crystalline corundum production will be carried out in JSC "The Quartz Glass Plant" in industrial autoclave (4 m3) and pilot-plant batch of doped corundum (1 tone of abrasive and 1 tone of luminophore) will be produced.
Produced corundum will be delivered to potential consumers for testing and marketing.
High quality of doped fine crystalline corundum as abrasive material allows to estimate it after marketing studies as valuable product in the market. Its approximate price can amount $15-25 per kg with production cost of $5 per kg. High industrial demands in effective abrasives can be satisfied by production of this material by JSC “The Quartz Glass Plant”. Plant’s production facilities allow to produce up to 2 thousand tones of corundum per year. This can solve the problem of employment of workers, engineers and scientists from military production sphere. In particular the group of authors took part in development of navigation system of wide range missiles.
Due to its great experience in production of crystalline quartz using hydrothermal technology the foreign collaborator (Sawyer Co., USA) can offer skilled assistance to Russian performer in development of new technology of doped fine crystalline corundum, organization of experimental production, economical estimations and marketing studies.