ZIRCONIUM POWDER MANUFACTURING PROCESS Russian patent published in 2007 - IPC B22F9/18 C22B34/14 

FIELD: nonferrous metallurgy.

SUBSTANCE: invention relates to manufacturing zirconium powder for making pyrotechnic articles, in particular explosive and inflammable mixtures. By-layers prepared powered mixture of potassium fluorocirconate and alkali metal chloride, preferably sodium chloride, at ratio 1:(0.15-0.6) and sodium metal in amount exceeding its stoichiometrically required amount by 10-20%. Preparation involves grinding of potassium fluorocirconate and alkali metal chloride to fineness below 50 μm as well as preliminary recrystallization of potassium fluorocirconate. Charge is heated to temperature 450-600°C, at which reduction reaction starts and during this reaction reaction mixture heats to 700-800°C and reduction of potassium fluorocirconate takes place. Reaction products are cooled to 400-650°C and freed of sodium through vacuum distillation at residual pressure 1.3-13.3 Pa for 0.5-2.0 h, after which they are discharged from reaction vessel and ground. Zirconium powder is washed with water to remove fluoride and chloride salts and then dried. Zirconium powder contains 95-98% of fine fractions, including fraction below 10 μm in amount 45-55%.

EFFECT: enhanced fineness of prepared zirconium powder end assured fire safety of the process.

8 cl, 3 ex