Diffusion of oxygen in growing zirconia films

Cox, B.; Pemsler, J. P.

doi:10.1016/0022-3115(68)90058-5

Cited by 134 publications

(41 citation statements)

References 7 publications

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“…A logarithmic graph of K versus reciprocal temperature is shown in Figure 5.3(b) for all isothermal measurements, together with values reported in previous works [102,104]. The value obtained in our measurements is roughly one to two orders of magnitude larger than the literature values, which may be expected because the very small grain size of our samples promotes grain boundary diffusion of oxygen through the oxide [105]. A least square line fit of the data then yields an activation energy of E a =0.60 0.09 eV for the oxidation process, comparable to the activation energy obtained from low-temperature oxidation data in the literature [102].…”

Section: Experimental Details and Resultssupporting

confidence: 74%

Scanning AC Nanocalorimetry and Its Applications

Xiao

Vlassak

2016

Fast Scanning Calorimetry

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This thesis presents an AC nanocalorimetry technique that enables calorimetry measurements on very small quantities of materials over a wide range of scanning rates (from isothermal to 3×10^3 K/s), temperatures (up to 1200 K), and environments. Such working range bridges the gap between traditional scanning calorimetry of bulk materials and nanocalorimetry. The method relies on a micromachined nanocalorimeter with negligible thermal lags between heater, thermometer, and sample. The ability to perform calorimetry measurements over such a broad range of scanning rates makes it an ideal tool to characterize the kinetics of phase transformations, reactions at elevated temperatures or to explore the behavior of materials far from equilibrium. We By combining scanning DC and AC nano-calorimetry techniques, we study the nucleation behavior of undercooled liquid Bi at cooling rates ranging from 10^1 to 10^4 K/s. Upon initial melting, the Bi thin-film sample breaks up into isolated islands. The number of islands in a typical sample is sufficiently large that highly repeatable nucleation behavior is observed, despite the stochastic nature of the nucleation process.We establish a data reduction technique to evaluate the nucleation rate from DC and AC calorimetry results. The results show that the driving force for the nucleation of melted Bi is well described by classical nucleation theory over a wide range of cooling rates. The proposed technique provides a unique and efficient way to examine nucleation kinetics v with cooling rates over several orders of magnitude. The technique is quite general and can be used to evaluate reaction kinetics in other materials.Lastly, we apply the scanning AC nanocalorimetry technique to study solid-gas phase reactions by measuring the change in heat capacity of a sample during reaction. We apply this approach to evaluate the oxidation kinetics of thin-film samples of zirconium in air. The results confirm parabolic oxidation kinetics with an activation energy of 0.59±0.03 eV. The nano-calorimetry measurements were performed using a device that contains an array of micromachined nano-calorimeter sensors in an architecture designed for combinatorial studies. We demonstrate that the oxidation kinetics can be quantified using a single sample, thus enabling high-throughput mapping of the composition-dependence of the reaction rate.vi

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Section: Experimental Details and Resultssupporting

confidence: 74%

Scanning AC Nanocalorimetry and Its Applications

Xiao

Vlassak

2016

Fast Scanning Calorimetry

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“…The value obtained in our measurements is roughly one to two orders of magnitude larger than the literature values, which may be expected because the very small grain size of our samples promotes grain boundary diffusion of oxygen through the oxide [ 30 ]. A least square line fit of the data then yields an activation energy of E a =0.60 ± 0.09 eV for the oxidation process, comparable to the activation energy obtained from low-temperature oxidation data in the literature [ 27 ].…”

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confidence: 47%

Kinetics of solid-gas reactions characterized by scanning AC nano-calorimetry with application to Zr oxidation

Xiao

Lee

Vlassak

2014

Applied Physics Letters

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Scanning AC nano-calorimetry is a recently developed experimental technique capable of measuring the heat capacity of thin-film samples of a material over a wide range of temperatures and heating rates. Here we describe how this technique can be used to study solid-gas phase reactions by measuring the change in heat capacity of a sample during reaction. We apply this approach to evaluate the oxidation kinetics of thin-film samples of zirconium in air. The results confirm parabolic oxidation kinetics with an activation energy of 0.59±0.03 eV. The nano-calorimetry measurements were performed using a device that contains an array of micromachined nano-calorimeter sensors in an architecture designed for combinatorial studies. We demonstrate that the oxidation kinetics can be quantified using a single sample, thus enabling high-throughput mapping of the composition-dependence of the reaction rate. a)

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“…In the case of oxygen, its solubility in zirconium is quite large, about 29 at% at ambient temperature [57]. This is a consequence of the relatively large size of the octahedral sites in the hcp lattice (see Figure 1).…”

Section: Oxidationmentioning

confidence: 99%

Modeling of Some Physical Properties of Zirconium Alloys for Nuclear Applications in Support of UFD Campaign

Glazoff¹

2013

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Zirconium-based alloys Zircaloy-2 and Zircaloy-4 are widely used in the nuclear industry as cladding materials for light water reactor (LWR) fuels. These materials display a very good combination of properties such as low neutron absorption, creep behavior, stress-corrosion cracking resistance, reduced hydrogen uptake, corrosion and/or oxidation, especially in the case of Zircaloy-4. However, over the last couple of years, in the post-Fukushima Daiichi world, energetic efforts have been undertaken to improve fuel clad oxidation resistance during off-normal temperature excursions. Efforts have also been made to improve upon the already achieved levels of mechanical behavior and reduce hydrogen uptake. In order to facilitate the development of such novel materials, it is very important to achieve not only engineering control, but also a scientific understanding of the underlying material degradation mechanisms, both in working conditions and in storage of used nuclear fuel.This report strives to contribute to these efforts by constructing the thermodynamic models of both alloys; constructing of the respective phase diagrams, and oxidation mechanisms. A special emphasis was placed upon the role of zirconium suboxides in hydrogen uptake reduction and the atomic mechanisms of oxidation. To that end, computational thermodynamics calculations were conducted concurrently with first-principles atomistic modeling.

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Diffusion of oxygen in growing zirconia films

Cited by 134 publications

References 7 publications

Scanning AC Nanocalorimetry and Its Applications

Scanning AC Nanocalorimetry and Its Applications

Kinetics of solid-gas reactions characterized by scanning AC nano-calorimetry with application to Zr oxidation

Modeling of Some Physical Properties of Zirconium Alloys for Nuclear Applications in Support of UFD Campaign

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