Vaporization of Strontium, Barium, Lanthanum, and Uranium from Mixtures of Urania, Zirconia, Steel, and Concretes at 2150 and 2400 K

Applied physical chemistry progress report, October 1991--September 1992

“…In earlier experiments, 3 In an earlier report, 4 DTA measurements of the U0 2 -CaO phase diagram were described. Solidus and liquidus temperatures were also presented for three types of concrete (limestone, limestone-sand, and siliceous) and for their mixtures at 27.5 wt% calcined concrete with 72.5 wt% U0 2 -ZrO 2 (1.6:1 mole ratio of U0 2 to ZrO 2 ).…”

“…The crystals were grown using the Czochralski technique, and the magnesium dopant level was determined to be 0.3% by spark source spectrometry. 3 1 The samples were dried under vacuum at 800*C for 4 h and then packaged in aluminum capsules, which were cold-welded shut in an inert helium atmosphere glovebox. The capsules were irradiated in a cadmium-lined neutron activation tube at the University of Illinois, UrbanaChampaign, for 3 hours at a power level of 1500 kW.…”

“…5 '' 6 Our assessment of the evidence led us, in the present analysis, to consider only FeZr 3 , which was assumed to be stoichiometric. The following Gibbs energies of formation of FeZr 2 and 9 FeZr 3 from the liquid elements were derived: for the reaction 1/3 Fe(e) + 2/3 Zr(Q) = 1/3 FeZr 2 (s), AG* = -38158 + 9.623T (2) and for the reaction 1/4Fe(Q) + 3/4Zr(Q) = 1/4FeZr 3 (s), AG* = -42007 + 16.736T (3) As shown in Fig. 5, the eutectic reported at 928C, 5 the eutectoid reported at 795*C,' 6 and the peritectoid reported at 885CC 1 " are well reproduced.…”