TANTALUM POWDER PRODUCING METHOD Russian patent published in 2004 - IPC

FIELD: powder metallurgy, possibly preparation of powders for making capacitors.

SUBSTANCE: method comprises steps of melting in fluid-tight reactor initial mixture of tantalum potassium fluoride and inert slag-generating salt; reducing tantalum potassium fluoride by means of metallic sodium at batch supplying into reactor melt sodium and tantalum potassium fluoride or mixture of the last with inert slag generating salt; setting relation of mass values of tantalum potassium fluoride and added inert slag-generating salt in initial mixture 0.4 - 1; setting relation of mass values of tantalum potassium fluoride and added inert slag-generating salt in melt initial mixture 0.3 - 0.8; setting relation of mass values of tantalum potassium fluoride in initial melt mixture and tantalum potassium fluoride batch supplied into reactor at reduction 0.2 - 1; adding tantalum potassium fluoride to reactor at rate 0.1 -0.5 kg/min per 100 sq. cm of reactor cross section area; adding liquid sodium into reactor at rate 0.05 - 0.1 kg/min per 100 sq. cm of reactor cross section area; sustaining reduction temperature 500 - 750 C. Invention provides preparation of powders with controllable specific surface in wide range 1 - 10 sq.m/g, nanocrytalline structure with crystal value 30 - 300 nm and small crystalline structure with crystal value 0.3 - 0.8 micrometers.

EFFECT: improved fineness of powder.

5 cl, 3 ex