TY - JOUR
T1 - Heat-induced redistribution of surface oxide in uranium
AU - Swissa, Eli
AU - Shamir, Noah
AU - Mintz, Moshe H.
AU - Bloch, Joseph
N1 - Funding Information:
The technical assistance of Mr. A. Kremner in preparation and annealing of the samples is thankfully acknowledged. This work was partially supported by a joint grant of the Israel Atomic Agency commission and the Israel Council for Higher Education.
PY - 1990/9/1
Y1 - 1990/9/1
N2 - The redistribution of oxygen and uranium metal at the vicinity of the metal-oxide interface of native and grown oxides due to vacuum thermal annealing was studied for uranium and uranium-chromium alloy using Auger depth profiling and metallographic techniques. It was found that uranium metal is segregating out through the uranium oxide layer for annealing temperatures above 450°C. At the same time the oxide is redistributed in the metal below the oxide-metal interface in a diffusion like process. By applying a diffusion equation of a finite source, the diffusion coefficients for the process were obtained from the oxygen depth profiles measured for different annealing times. An Arrhenius like behavior was found for the diffusion coefficient between 400 and 800°C. The activation energy obtained was Ea = 15.4 ± 1.9 kcal/mole and the pre-exponential factor, D0 = 1.1 × 10-8cm2/s. An internal oxidation mechanism is proposed to explain the results.
AB - The redistribution of oxygen and uranium metal at the vicinity of the metal-oxide interface of native and grown oxides due to vacuum thermal annealing was studied for uranium and uranium-chromium alloy using Auger depth profiling and metallographic techniques. It was found that uranium metal is segregating out through the uranium oxide layer for annealing temperatures above 450°C. At the same time the oxide is redistributed in the metal below the oxide-metal interface in a diffusion like process. By applying a diffusion equation of a finite source, the diffusion coefficients for the process were obtained from the oxygen depth profiles measured for different annealing times. An Arrhenius like behavior was found for the diffusion coefficient between 400 and 800°C. The activation energy obtained was Ea = 15.4 ± 1.9 kcal/mole and the pre-exponential factor, D0 = 1.1 × 10-8cm2/s. An internal oxidation mechanism is proposed to explain the results.
UR - http://www.scopus.com/inward/record.url?scp=0025484099&partnerID=8YFLogxK
U2 - 10.1016/0022-3115(90)90315-E
DO - 10.1016/0022-3115(90)90315-E
M3 - Article
AN - SCOPUS:0025484099
SN - 0022-3115
VL - 173
SP - 87
EP - 97
JO - Journal of Nuclear Materials
JF - Journal of Nuclear Materials
IS - 1
ER -