Microstructure of oxide layers formed on zirconium alloy by air oxidation, uniform corrosion and fresh-green surface modification

Sawabe, Takashi; Sonoda, Tatsuhiko; Furuya, Masahiro; Kitajima, S.; Kinoshita, Motoyasu; Tokiwai, Moriyasu

doi:10.1016/j.jnucmat.2011.05.028

Cited by 11 publications

(4 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…All these factors depend on the oxidation temperature and time, composition and fugacity of a medium, and chemical and phase composition of an alloy [23]. The obtained results here correspond to the previous reports regarding the temperature dependence of the oxide layer growth [25,[61][62][63][64][65][66][67], the complex multilayer and multiphase structure [68][69][70][71], growth of the oxide layer in columnar grains [68,72], and the appearance of porosity [25,33,[73][74][75] and cracks [76][77][78][79]. Interestingly, it was also noted that a severe descaling of the oxide layer appeared in these investigations at a relatively high temperature.…”

Section: Characteristics Of Oxide Layerssupporting

confidence: 89%

Hydrogen Embrittlement and Oxide Layer Effect in the Cathodically Charged Zircaloy-2

et al. 2020

View full text Add to dashboard Cite

The present paper is aimed at determining the less investigated effects of hydrogen uptake on the microstructure and the mechanical behavior of the oxidized Zircaloy-2 alloy. The specimens were oxidized and charged with hydrogen. The different oxidation temperatures and cathodic current densities were applied. The scanning electron microscopy, X-ray electron diffraction spectroscopy, hydrogen absorption assessment, tensile, and nanoindentation tests were performed. At low oxidation temperatures, an appearance of numerous hydrides and cracks, and a slight change of mechanical properties were noticed. At high-temperature oxidation, the oxide layer prevented the hydrogen deterioration of the alloy. For nonoxidized samples, charged at different current density, nanoindentation tests showed that both hardness and Young’s modulus revealed the minims at specific current value and the stepwise decrease in hardness during hydrogen desorption. The obtained results are explained by the barrier effect of the oxide layer against hydrogen uptake, softening due to the interaction of hydrogen and dislocations nucleated by indentation test, and hardening caused by the decomposition of hydrides. The last phenomena may appear together and result in hydrogen embrittlement in forms of simultaneous hydrogen-enhanced localized plasticity and delayed hydride cracking.

show abstract

Section: Characteristics Of Oxide Layerssupporting

confidence: 89%

Hydrogen Embrittlement and Oxide Layer Effect in the Cathodically Charged Zircaloy-2

et al. 2020

View full text Add to dashboard Cite

show abstract

“…The detection of ZrO 2 is agreement with Zr-enriched oxidized surfaces observed after exposure to both air and steam. In addition, the presence of ZrO 2 is in agreement with the vast body of study on Zircaloy[7, 9, 10, 29,65,66,67,68,69,70,71,72,73].…”

supporting

confidence: 88%

Characterization of oxidation layers on novel nuclear fuel cladding alloys

Copeland-Johnson¹

View full text Add to dashboard Cite

show abstract

“…There are some ideas and proposed methods for increasing the claddings' corrosion resistance: (i) develop new alloys with special composition and microstructure (for example: M5 from AREVA or ZIRLO from Westinghouse [9]); (ii) application of new materials that are resistant to water corrosion (for example: SiC [10]); (iii) modification of the surface layer of Zry by the so-called "Fresh-Green" process [11]; (iv) modification of the surface layer by irradiation with ion beams [12], pulsed electron beams [13], and plasma beams [12,14]; (v) incorporation of rare earth elements to the surface of Zry [15]; (vi) a protective layer formed on the Zry surface (for example: on the base of silicon [16,17] and ceramics MAX, where MAX phases are layered, hexagonal carbides and nitrides, which have the general formula: Mn+1AXn (MAX), where n = 1 to 3, and M is an early transition metal, A is an A-group (mostly IIIA and IVA or groups 13 and 14) element, and X is either carbon and/or nitrogen [18] or FeCrAl alloys [19]).…”

Section: Introductionmentioning

confidence: 99%

Multi-Elemental Coatings on Zirconium Alloy for Corrosion Resistance Improvement

et al. 2022

View full text Add to dashboard Cite

Zirconium alloys are commonly used as a cladding material for fuel elements in nuclear reactors. This application is connected with zirconium alloy’s good resistance to water corrosion and radiation resistance under normal working conditions. In the case of severe accident conditions, the possibly very fast oxidation of zirconium alloys in steam or/and air atmosphere may result in the intense generation of hydrogen and explosion of the hydrogen oxide mixture. The development of a solution to minimize the aforementioned risk is of interest. One of the actual concepts is to improve the oxidation resistance of Zr alloy cladding with protective coatings. This study aimed to develop, form, and investigate new coatings for zirconium alloy Zry-2. Multi-elemental Physical Vapour Deposition (PVD) coatings with Cr, Si, and Zr were considered for Institute of Nuclear Chemistry and Technology) INCT as corrosion protective coatings for nuclear fuel claddings. Heat treatment at 850–1100 °C/argon, air oxidation processes at 700 °C/1–5 h, and a long-term corrosion test in standard conditions for Pressure Water Reactor (PWR) reactors (360 °C/195 bar/water simulating the water used in PWR) were carried out. Initial, modified, and oxidized materials were characterized with Scanning Electron Microscopy (SEM) (morphology observations), Energy Dispersive Spectroscopy (EDS) (elemental composition determination), and X-ray Diffraction (XRD) (phase composition analysis). Slower oxidation processes and a smaller oxidation rate, in the case of modified material investigations, were observed, as compared with the unmodified material. The obtained results displayed a protective character against the oxidation of formed layers in the defined range of parameters in the process.

show abstract

Microstructure of oxide layers formed on zirconium alloy by air oxidation, uniform corrosion and fresh-green surface modification

Cited by 11 publications

References 13 publications

Hydrogen Embrittlement and Oxide Layer Effect in the Cathodically Charged Zircaloy-2

Hydrogen Embrittlement and Oxide Layer Effect in the Cathodically Charged Zircaloy-2

Characterization of oxidation layers on novel nuclear fuel cladding alloys

Multi-Elemental Coatings on Zirconium Alloy for Corrosion Resistance Improvement

Contact Info

Product

Resources

About