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|Title:||The Kinetics and Thermodynamics of Oxygen in Nickel, Palladium, and Niobium-Vanadium Solid Solutions (Diffusion, Solubility, Electrochemistry)|
|Department / Program:||Metallurgy and Mining Engineering|
|Degree Granting Institution:||University of Illinois at Urbana-Champaign|
|Abstract:||Solid-state electrochemical measurements using alternative experimental procedures were made with the double cell Ni + NiO(VBAR)ZrO(,2) + Y(,2)O(,3)(VBAR)Ni or Pd(VBAR)ZrO(,2) + Y(,2)O(,3)(VBAR)Ni + NiO to determine the kinetic and thermodynamic functions of oxygen in solid nickel and palladium. Non-steady state diffusion of oxygen in the specimen was caused by applying a preselected potential between the reference and specimen electrodes and was monitored by measuring time-dependent potentials and/or currents. The following results were obtained for the diffusivities and terminal solubilities of oxygen in nickel and palladium: D (Ni) = 4.9 x 10('-2) exp(-((164 kJ/mole)/RT)) cm('2)/sec (850-1400(DEGREES)C); C(,o)('s) (Ni) = 9.1 exp(-((56 kJ/mole)/RT)) at% (800-1000(DEGREES)C); D (Pd) = 1.03 x 10('-5) exp(-((98 kJ/mole)/RT)) cm('2)/sec (900-1150(DEGREES)C); C(,o)('s)(Pd) = 5.4 x 10('-2) exp(-((117 kJ/mole)/RT)) at% (900-1150(DEGREES)C).
Using single galvanic cells with zirconium sinks, the diffusivities of oxygen in Nb-V alloys were measured. Vanadium atoms trap oxygen more strongly in niobium than niobium atoms do in vanadium. The trap energy does not appear to depend on the substitutional concentration, up to 10 at%. An attempt was made to find correlations between the kinetic and thermodynamic behavior of oxygen in Nb-V alloys.
Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1985.
|Date Available in IDEALS:||2014-12-16|
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Dissertations and Theses - Metallurgy and Mining Engineering
Graduate Dissertations and Theses at Illinois
Graduate Theses and Dissertations at Illinois