Abstract: A two-phase reduction method for producing tantalum powder includes loading an unheated reaction vessel with a layer of K2TaF7, then a layer of solid sodium metal, and then followed by a layer of solid diluent salt. A first heating phase is used to promote the solid state reduction of the layer of K2TaF7, which results in the production of very fine tantalum particles while minimizing tantalum crystal growth. A second heating phase is then used to melt the contents of the reactor vessel and react primary quantities of sodium metal and K2TaF7 to produce tantalum powder. In certain embodiments, the fine tantalum particles produced during the first heating phase serve as the nucleation sites needed for tantalum crystal growth in the second heating phase.

Abstract: Porous microparticles of high-purity tantalum may be processed in a vacuum plasmatron using a hollow cathode and spraying apparatus in which the coolant is in the form of a metal surface. In one embodiment, the initial powder of tantalum is introduced through a coaxial hole in a hollow cathode and supplied to a vertical column of plasma by inert gas and exposed to heating to temperatures close to the melting point of tantalum. The atomizing tantalum particles are directed through a hole in the anode and collide with a rotating inclined tantalum substrate and cooled from within water, thereby flattened and solidifying the particles.

Abstract: Porous microparticles of high-purity tantalum may be processed in a vacuum plasmatron using a hollow cathode and spraying apparatus in which the coolant is in the form of a metal surface. In one embodiment, the initial powder of tantalum is introduced through a coaxial hole in a hollow cathode and supplied to a vertical column of plasma by inert gas and exposed to heating to temperatures close to he melting point of tantalum. The atomizing tantalum particles are directed through a hole in the anode and collide with a rotating inclined tantalum substrate and cooled from within water, thereby flattened and solidifying the particles.

Abstract: The production of tantalum powder having a low impurity level is provided by a method in which potassium heptafluotantalate is added to a mixture of alkali metal halides in reactor vessel in which the internal surface and auxiliary input accessories of the reactor are covered with a tantalum coating. In one embodiment, the production of tantalum powder with low impurity level includes depositing a protective tantalum coating onto an internal surface of the reactor vessel and auxiliary accessories of a reactor by electrolysis of a mixture of alkali metals halides and potassium heptafluotantalate.