Method for production of tantalum and niobium powders with highly developed surface

A metal powder having substantially increased BET surface area prepared from an initial powder of a metal selected from a group consisting of tantalum, niobium and mixtures thereof by a method comprising the following steps:

• mechanically alloying the initial selected metal powder with a powder of an auxiliary substance having relatively weak corrosion resistance as compared to that of the selected metal, thereby providing interaction between the particles of the selected metal and the substance powders, wherein the mechanical alloying is continued until a solid solution of the selected metal and the substance is obtained, in which the selected metal particle has a substantially developed surface area and is at least partly wetted with said substance substantially within a surface region of the selected metal particle;
• and
• removing the substance from the obtained solid solution, thereby leaving the selected metal particles with the substantially developed surface area free from the substance;
• wherein said increased surface area reaches 40 m2/g and more.