Phase transformations in Pu–Ga and Pu–Al alloys: Effects of pressure and temperature on kinetics of δ-phase decomposition

Abstract

Pressure effected evolution of equilibrium and metastable binary Pu–Ga (Al)-phase diagrams is discussed. With an increase in pressure δ-solid solution region decreases and disappears, which leads to a change of phase diagram type. In experiments and via thermodynamic calculations boundaries of δ-phase region were established at pressure varying from the atmospheric one to ∼1 GPa. Temperature of δ-phase eutectoid transformation versus pressure was determined; a fragment pressure–temperature–composition ( PTC) diagram was constructed, parameters of four-phase equilibrium were found. Influence of static pressure on δ-phase decomposition kinetics is demonstrated, feasibility of decomposing effected by loading with high intensity waves is assessed.