The invention relates to a preparing method of low-
oxygen large-dimension high-purity
hafnium powder. The purity of the low-
oxygen large-dimension high-purity
hafnium powder is as high as 99.99 weight percent, the
oxygen content is less than 0.2 percent, and the
granularity is greater than 1mu. m. A preparing process comprises the following steps that a,
hafnium oxide powder, reducing agents and
molten salt are contained into a
crucible; b, the
crucible is placed into a reaction tank,
vacuum pumping is carried out after the device is sealed, then,
argon gas is filled for washing, heating reduction is carried out, then, constant-temperature heat-insulation reduction is carried out, and cooling and furnace discharging are carried out after the reduction completion; c, obtained products are firstly washed by acid and are then washed by de-ionized water, then, sieving and
drying are carried out, and the low-oxygen large-dimension high-purity
hafnium powder can be obtained. The
molten salt system adopted by the method provided by the invention has the advantages that the
oxygen content in the
hafnium powder can be effectively removed, meanwhile, the dimension of the
hafnium powder can be controlled, the friction
spontaneous combustion of the hafnium powder is prevented, and safety and
controllability are realized.