| 摘要 |
<p>Ores containing tantalum and niobium or metallurgical bye-products containing such elements in the form of oxide compounds are reduced by means of calcium and aluminium conjointly, with the application of external heat, the tantalum and niobium being completely or substantially completely reduced. The calcium and aluminium may be used in the form of alloys with tantalum and/or niobium. A metal, such as iron, may be added to the charge or reducing bath before, during, or after treatment to obtain an alloy, or the reducing operation may be carried out in a bath of molten metal or alloy; the alloying metal may be added to the charge or bath in oxide form. The slags, residues, or bye-products of the reducing operation may be treated with calcium, and/or aluminium to produce an alloy of tantalum and niobium with calcium and/or aluminium; such alloy may be used as a reducing agent for the primary material. The reduction may be effected in an induction, arc, radiating, crucible, or flame furnace. In an example, an alloy containing 25 per cent of calcium and 75 per cent of aluminium is used to reduce a concentrate, iron and fluorspar being added, the resulting alloy containing tantalum, niobium, iron, manganese, silicon, and aluminium. Specification 467,484 is referred to.</p> |
