THERMALLY SPRAYED POWDER AND THE METHOD OF ITS PRODUCTION Russian patent published in 2007 - IPC C01G37/27 

FIELD: chemical industry; the thermally sprayed powders and the methods for their production.

SUBSTANCE: the invention is pertaining to the method of production of the thermally sprayed powders and may be used in production of the powders out of the chromium dioxide for the thermally sprayed wear-resistant coatings. The thermally sprayed powder contains from 45 up to 99 mass % of chromium dioxide and from 1 up to 55 mass % of alpha aluminum oxide, and less than 50 shares per one million of the alkaline-metals and the alkaline-earth metals stabilizing chromium in its hexavalent state. The powder particles have primarily the single-phase crystalline structure with the aluminum oxide share in other phases, except for the alpha phase, of no more than 10 mass % of the full contents of the aluminum oxide. The method of production of the thermally sprayed powder includes: stirring action of the aluminum oxide powder containing the impurities of the alkaline- metals and the alkaline-earth metals of no more than 120 shares per one million of each element with the chromium dioxide powder, which also has less than 120 shares per one million of the impurities of the alkaline-metals and the alkaline-earth metals stabilizing chromium in the hexavalent state; burning of the mixture at the temperature of 1300-1500°С. The invention allows to reduce formation of the toxic compounds of the hexavalent chromium during the thermal spraying of the wear-resistant powders of chromium dioxide.

EFFECT: the invention ensures the reduced formation of the toxic compounds of the hexavalent chromium during the thermal spraying of the wear-resistant powders of chromium dioxide.

6 cl, 1 dwg