ИСТИНА

In present paper the investigation of influence doping by chrome, manganese or europium on optical and mechanical characteristics of corundum are represented. The doping carried out during process synthesis of corundum in supercritical water fluid in the laboratory autoclaves at 400°C and under water pressure 26 – 30 MPa. The optimal concentrations of chrome and manganese are determined. The corundum doped by chrome has a maximum of intensity of luminescence band 694 nm at concentration Cr3+ ~ 0.1 %. In same field of chrome concentrations the corundum crystals have maximal crushing strength. The maximum of intensity of luminescence band 678 nm of corundum doped by manganese is observed at concentration of manganese 2x10-3 %. In the doping case of corundum by europium the intensity of luminescence of corundum is proportional increased with the rise of concentration Eu3+ in range of 0.05 – 1%. The formation of doped corundum structure in water fluid leads to the inclusion into corundum crystal lattice of hydroxyls, which interact with doping ions and with oxygen vacancies and generate composite defects. It was concluded, that the interaction of doping ions with each other and with point defects of corundum structure is accompanied by change of composition of defect complexes and their influence on properties of corundum.