Density and viscosity of liquid Pu-U alloys

Density and viscosity determinations of liquid Pu-U alloys were made for five compositions, 5.5, 10.8, 16.6, 22.4, and 28.5 wt pct U, from near their liquidus temperatures to above 800°C. A vacuum pycnometric technique was used for the density determinations and an oscillating cup viscometer for the viscosity determinations. The partial molar volume of uranium was decreased approximately 15 pct in solutions containing up to 10.8 wt pct U and approached the normal molar volume at higher uranium concentration. The partial molar volume of plutonium changed by only 1 pct over the entire composition range. The viscosity of the alloys up to 10.8 pct U increased more rapidly than predicted from the pure components. Formerly with Monsanto Research Corp.