METHOD FOR PRODUCTION OF HAFNIUM BY VACUUM ARC REMELTING Russian patent published in 2016 - IPC C22B9/20 C22B34/14 

FIELD: chemistry.

SUBSTANCE: invention relates to obtaining hafnium ingots. Pressed briquettes of charge hafnium material with density of briquette not less than ρ_br = 7.2 g/cm³. Consumable electrode is formed by electron beam welding of briquettes. First vacuum arc remelting of obtained consumable electrode with ARC current force I = K₁×Ding is made, where the coefficient of proportionality K₁ = 70-220 a/cm, Ding -melted ingot diameter, cm, and then the second vacuum arc remelting in two-stage mode is made, wherein the arc current intensity of the first stage I₁ = K₂×Ding, where the coefficient of proportionality is K₂ = 220-350 A/cm, and the arc current intensity of the second stage I₂ = K₃×I₁, where the coefficient of proportionality is K₃ = 0.25-0.5. As a charge hafnium material the electrolytic hafnium powder and additionally milled recycled and/or iodide hafnium can be used.

EFFECT: higher quality of produced hafnium ingots due to reduced casting defects.

3 cl, 1 tbl, 7 ex