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Removal of mechanical additives from the surface of cast niobium; pp. 241–246

Full article in PDF format | doi: 10.3176/proc.2008.4.06

Valeri Gorkunov, Mihhail Kogtev, Rein Munter


A combined method of the utilization of deposits from the shaft furnace of niobium production consisting of the stages of thermomechanical treatment, hydrogenation, grinding, and separation was elaborated in industrial conditions. This method enables to clean the surface of metallic niobium from slag (3CaO·5Al2O3) and from graphite additives. Altogether more than 20 tonnes of Nb–Al (5%) powder meeting the requirements presented to commercial technical niobium was produced. Application of the proposed utilization technology increases the profitability of pure niobium production by 0.2–0.3%. The results obtained can be used for cleaning other refractory metals from slag and other surface additives.


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