Formation of Metastable Structures and Amorphous Phases in Plutonium-Based Systems Using the Triode Sputtering Technique

The triode sputtering technique has been used to obtain metastable crystalline and amorphous phases in ten binary systems of Pu with Si, Al, vanadium, Fe, cobalt, Pd, Ta, rhenium, Os and Ir. The lattice parameters and near-neighbor distances evaluated with X-ray diffraction frequently show deviations from an assumed Vegard's Law which can be interpreted in relation to the changing electronic configuration and corresponding size of the Pu atom. When the Egami and Waseda criterion is applied to predict the possible range of amorphous phase formation, in terms of the atomic volume of the component atoms, the observed range exceeds the predicted range in Pu-rich alloys because the atomic size of the Pu atoms changes on alloying. 15 ref.--AA