A study on preparation of copper-niobium composite by aluminothermic reduction of mixed oxides

Cu-Nb composites have come into prominence because of their high strength and high electrical conductivity. A number of preparative techniques have received attention among the investigators due to difference in melting point, density and crystal structure of the constituents. In the present paper a simple, easy to scale up, non-furnace process involving co-reduction of mixed oxides (CuO, Nb2O5) with aluminium in the presence of slag fluidizer CaO has been attempted to prepare a Cu-2.5Nb (wt%) composite. A typical charge composition of about 58.2% CuO, 3.5% Nb2O5 23.3% CaO and 15% Al (specific heat 715 kcal/kg) resulted in a Cu-Nb product with 83% yield of nearly targeted composition. As reduced composite was homogenized by arc melting. Remelted and consolidated composite was drawn into wires of <0.5 nun diameter to convert the dendritic niobium phase into the filamentary form. Property evaluation studies such as optical metallography, hardness, electrical resistivity measurements etc. have been carried out. (C) 2002 Elsevier Science B.V. All rights reserved.