The Uranium-Rhenium Alloy System (open access)

The Uranium-Rhenium Alloy System

Abstract The phase diagram of the uranium-rhenium alloy system is presented along with a discussion on transformation kinetics of the uranium solid solutions. The phase diagram is of the double eutectic type with the intermediate phase having the composition URe2. This phase exhibits allotropy at 180°C and melts congruently at 2200°C. URe2 reacts sluggishly with the uranium solid solutions below 750°C to form the peritectoid compound U2Re. Eutectic reactions occur at 1105° and 2105°C at respective compositions of 10.5 and 65.5 wt. % Re. Eutectoid reactions occur at 643° and 681°C at compositions of 1.4 and 6 wt. % Re, respectively. The maximum solubility of rhenium in α uranium is about 0.4 wt. % at 643°C and in β uranium is 1.9 wt. % at 681°C. The solubility of rhenium in γ uranium is 6 wt. % at 681°C and increases to about 7 wt. % at 975°C. The solubility of uranium in rhenium is 0.6 wt. % at room temperature with little variation up to 2000°C. Alloys of β and γ uranium containing more than about 1.2 and 7 wt. % Re respectively, can be readily supercooled to room temperature. Rapid cooling of γ alloys containing less than about …
Date: January 14, 1963
Creator: Jackson, R. J. (Robert James), 1929-; Williams, D. E. & Larsen, W. L.
System: The UNT Digital Library
Pressure-Volume-Temperature Measurements on Solids (open access)

Pressure-Volume-Temperature Measurements on Solids

From abstract: "The results of recent measurements on the equations of state of sodium and xenon are discussed. The experimental data for each of these are analyzed to show that the isothermal compressibility is solely a function of volume within experimental accuracy. The basic differences between the low temperature PV relationships for sodium and xenon are shown to be easily understandable in terms of the elementary theories of these substances. The range of experimental pressures (to 20 kbars) and temperatures (20°K to the triple point) is sufficiently great so as to produce significant changes in the lattice thermal properties in each case. These changes are indicated through the use of zero pressure heat capacity data in combination with the equation of state data to calculate the volume and temperature dependence of the Debye Θ. The result is quite spectacular for xenon, where a pressure of 20 kbars roughly doubles ΘD."
Date: May 14, 1963
Creator: Swenson, C. A.
System: The UNT Digital Library