Preparation of U-Nb alloy from oxide precursors by direct oxide electrochemical reduction method

Abstract

The aim of the present study was to prepare U-7 wt% Nb alloy by the direct oxide electrochemical reduction (DOER) method. The alloy was prepared from the mixed oxide precursors namely, UO2 and Nb2O5. When the precursors were sintered in a reducing atmosphere of Ar-8 vol% H2, Nb2O5 was converted into NbO2. Subsequently, the mixed oxide pellet (UO2-NbO2) was reduced by the lithium metal, electrochemically generated from a molten LiCl-1 wt% Li2O bath at 700 °C. The electro-lithiothermic reduction was performed by constant current electrolysis mode with a mixed oxide pellet as the cathode and platinum as the anode. The reduction pathways of the individual oxides and the mixture were established using cyclic voltammetry and potentiostatic electrolysis techniques. The reduced alloy was characterized by XRD and SEM-EDS. These results confirmed the formation of U-Nb alloy. The composition of the alloy was determined by EDS, EDXRF and chemical analysis.