METHOD OF PRODUCTION OF HAFNIUM OR ZIRCONIUM AND THEIR ALLOYS Russian patent published in 2002 - IPC

FIELD: metallurgy. SUBSTANCE: proposed method consists in calcium thermal reduction from hafnium or zirconium tetrafluoride in presence of aluminum in the amount 0f 3.5 to 10mass-% relative to sum of its and hafnium or zirconium. Used as starting fluorides are non-sublimated hafnium or zirconium tetrafluorides subjected to vacuum thermal treatment at temperature of 300 to 600 C in inert gas atmosphere or in vacuum at temperature of 600 to 700 C before reduction followed by stabilization in inert-gas atmosphere in vacuum at temperature of 600 to 700 C. EFFECT: facilitated procedure; increased yield of hafnium or zirconium. 2 cl