Neptunium-plutonium alloys have been examined over the complete range of compositions using thermal analysis, dilatometric and X-ray techniques. The Blouson Femme Parajumpers probable form of the constitution diagram has been determined, the most noteworthy feature being the extremely high solubilities of neptunium in the monoclinic α and β phases of plutonium.
An intermediate phase exists Doudoune Parajumpers Pjs at high temperatures at the plutonium-rich end of the system; its crystal structure is complex but an orthorhombic cell has been tentatively assigned to it with , , for a 19 wt.% neptunium alloy at 375°C. The relation of this cell to the cubic ζ-plutonium-uranium and δ-neptunium-uranium phases is discussed.
γ-neptunium and ε-plutonium are completely miscible and by extrapolation of the high temperature lattice parameters a value of 3.518 Å was obtained for the γ-neptunium parameter at 500°C. There is appreciable solubility of plutonium in the α and β phases of neptunium, although the exact values are not known. The solidus shows a marked depression in the middle of Magasin Parajumpers Belgique the system and only varies slowly with composition over a large part of the diagram.