Electrodeposition of niobium from molten salts

Abstract

Niobium as well as the other refractory metals (4th, 5th and 6th columns of periodictable of elements), except chromium, cannot be electrodeposited from aqueous medium. Nevertheless, these metals can be obtained from alkali halides due to the highdecomposition voltage of these solvents. Electrodeposition can be divided intoelectrowinning, electroplating, electrorefining and electroforming. The aim of this workis to present our results on the three latter topics for niobium in alkali fluoride melts. Theeffect of electrolysis parameters, such as cathodic current density and temperature oncurrent efficiency, deposit morphology, microstructure, grain size and niobium purity isdiscussed. Niobium electroplating was performed on wires, tubes, plates and cathodes ofcomplex shapes in order to study the influence of the cathode shape and the anodecathodedistance on coating distribution. Corrosion data of niobium electroplates inmineral acid media are also shown. Some Nb electroforms are also presented. © 2010 by Nova Science Publishers, Inc. All rights reserved.