Tantalum and niobium carbides obtention by carbothermic reduction of columbotantalite ores

Abstract

Tantalum and niobium carbides are characterized by its high hardness and chemical corrosion resistance. Both carbides, but mainly TaC, are used in hard metals (sintered carbides), together with other carbides, to manufacture cutting tools and dies and in special machining applications involving mechanical shock at high temperature. Its use as reinforcement of wear resistant materials through powder metallurgy techniques are being investigated. However, the use of TaC is usually limited because of its high cost. Therefore tantalum carbide with niobium content, which is cheaper, is used. In this work the obtention of complex tantalum and niobium carbides from a Spanish columbotantalite ore is studied through a relatively cheap and simple process as it is carbothermic reduction. Concentration of the ore, its reduction and the characterization of products are described.