Synthesis and Structural Characterization of U-Zr-Nb Alloys

Abstract

U-xZr-yNb alloys with values of x varying from 32% to 50% (wt.%Zr) and y varying from 6% to 10% (wt.%Nb) were produced by the arc melting technique. The effect of the addiction of zirconium and niobium on the phase stabilization of γ-U, lattice parameter, microstructure and elemental composition were examined by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscope (EDS) techniques. The alloys crystallized in a cubic symmetry composed by a γ-U(Zr,Nb) matrix and β-Zr small precipitates, when the content of zirconium and niobium is up to 55 wt.%. With further additions, e.g. 60 wt.%, was observed a highly enriched macrosegregation of β-Zr. It was also observed that the cell size of the γ-U(Zr,Nb) phase increase with the addition of Zr and Nb. The lattice parameter curve behavior as a function of zirconium and niobium deviates from a linear behavior at around x ≈ 50 and y ≈ 10 wt.%.