Method for producing alloy powders based on titanium metal

A method for producing alloy powders based on titanium metal including the following stages:

• a) hydrolysis of an aqueous solution of titanium-containing salt with the release of a precipitate of titanium oxides and/or hydroxides to subsequently obtain primary particles of crystalline titanium oxide with a particle size distribution of 5-50 μm;
• b) washing and filtration of the formed precipitate of titanium oxides and/or hydroxides;
• c) precipitation of dopant oxides and/or hydroxides on the titanium oxides and/or hydroxides precipitate, by adding dopant salts to a slurry of the titanium oxides and/or hydroxides precipitate with a pH in the range of 0.5-12 to form a reaction mass, then stirring the reaction mass and adjusting the pH of the slurry to the range of 1.5-10.0 using aqueous solutions or slurries of alkaline reagents or using acidic reagents;
• d) filtration of the reaction mass to separate a cake of titanium oxides and/or hydroxides precipitate with dopant oxides and/or hydroxides precipitated on it from a mother liquor and washing the cake;
• e) calcination of the titanium oxides/hydroxides precipitate with precipitates of dopant oxides and/or hydroxides precipitated on it at a temperature of 400-1300° C. for 0.5-20 hours to obtain a solid solution of dopant oxides in titanium oxide;
• f) milling of a powder of the solid solution of dopant oxides in titanium oxide to form a milled powder;
• g) formation of feedstock elements from the milled powder of the solid solution of dopant oxides in titanium oxide with a strength of at least 10 kg per 1 cm2 regardless of which side the load is applied to the feedstock element;
• h) reduction of the feedstock elements using a reducing agent, during which 15-75% of the calculated amount of the reducing agent is loaded into a crucible, on a layer of which feedstock elements are installed;
• the remaining 25-85% of the calculated amount of the reducing agent being loaded on the surface of the feedstock elements;
• after that an inert filler is loaded onto the surface of the reducing agent, the amount of an inert filler being 10-1000% of the feedstock elements weight;
• i) quenching of the reaction mass comprising soaking in water for 1-48 hours;
• j) neutralization of the reaction mass, during which the pH of the reaction mass is maintained at a level of more than 0.5, using an acid selected from the group consisting of acetic acid, hydrochloric acid, and nitric acid;
• k) milling of the reaction mass to form a titanium metal slurry, during which the pH of the reaction mass is maintained in the range of 0.5-7 and when the pH rises above said range, an acid selected from the group consisting of acetic acid, hydrochloric acid, and nitric acid is introduced into the reaction mass;
• l) washing the titanium metal slurry to remove formed reaction products, inert filler, and residues of unreacted reducing agent, and filtration until specific electrical conductivity of 10% slurry of titanium metal in water is less than 100 μS/cm;
• m) drying of the powder resulting from Stage 1);
• n) reduction of the powder obtained at Stage m), using a reducing agent, during which a layer of the reducing agent is placed on the bottom of the crucible, and then a layer of the powder to be reduced is placed on it, so that the mass ratio of the thickness of the reducing agent layer covering the bottom of the crucible to the powder to be reduced is in the range from 1:35 to 2:1, covering the layer of the powder to be reduced again by a new layer of the reducing agent, and repeating this procedure until the crucible is fully loaded from top to bottom;
• o) quenching of the reaction mass comprising soaking in water for 1-48 hours;
• p) neutralization of the reaction mass, during which the pH of the reaction mass is maintained at a level of more than 0.5, using an acid selected from the group consisting of acetic acid, hydrochloric acid, and nitric acid;
• q) milling of the reaction mass, during which the pH of the reaction mass is maintained in the range of 0.5-7 and when the pH rises above said range, one of acetic acid, hydrochloric acid, and nitric acid is introduced into the reaction mass;
• r) washing the titanium metal slurry to remove formed reaction products, inert filler, and residues of unreacted reducing agent, and filtration until specific electrical conductivity of 10% slurry of titanium metal in water is less than 100 μS/cm;
• s) drying of a powder resulting from Stage r) and a classification of a finished product in an atmosphere of an inert gas selected from the group consisting of argon, helium, and nitrogen having a dew point of less than −20° C. and a temperature less than 80° C.