Three corrosion resistant uranium base alloys were corrosion-tested in high temperature water: U-5% Zr-1½% Nb, U-3% Nb-0.5% Sn, and U-3.8% Si. Only the U-3.8% Si alloy retained any degree of corrosion resistance after burnups in excess of 0.1 at. %. Low burnup did not adversely affect the corrosion resistance of the diffusion bond between U-2% Zr alloy and its Zircalloy-2 cladding.