Shift in low-frequency vibrational spectra measured in-situ at 600 °C by Raman spectroscopy of zirconia developed on pure zirconium and Zr–1%Nb alloy

doi:10.1016/j.molstruc.2016.03.001

Journal of Molecular Structure

Volume 1126, 15 December 2016, Pages 186-191

https://doi.org/10.1016/j.molstruc.2016.03.001 Get rights and content

Highlights

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Raman analysis allows to distinguish tetragonal and monoclinic bands of ZrO₂.
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Shift of low frequency monoclinic band can be used to calculate stress in ZrO₂.
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During corrosion similar zirconia phases develop on pure zirconium and its alloy.
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Small amount of tetragonal phase have been observed in the external part of ZrO₂.
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Pure zirconium can be used as analogues for alloy studies.

Abstract

In this study displacement of monoclinic bands of zirconia were investigated in the function of oxidation time using the Raman spectroscopy technique. Oxidations were performed on pure zirconium and zirconium alloy in-situ at 600 °C for 6 h. Analysis of the absolute intensities as well as the positions of the characteristic for monoclinic and tetragonal phase Raman bands were performed. Reported results has highlighted that monoclinic phase of zirconia undergoes a continuous band displacement, individual for each Raman mode. Recorded shift of low frequency vibrational spectra of monoclinic phase was employed to study stress developed in zirconia during high temperature oxidation – herein called as growing stress. In addition, based on the Raman band intensity we discuss observed transition of the metastable tetragonal phase to stable monoclinic phase. Reported results, for the first time showed that studied metals (pure zirconium and its alloy) behave similarly in terms of band shift. However the resulting value of growing stress associated to the band displacement is slightly different in regards of individual band and studied sample.

Graphical abstract

Introduction

Raman spectroscopy is a powerful tool to study structural changes developed in the material during high temperature treatment [1]. Recent advances in this technique, allow one to collect information recorded during oxidation process, i.e. in in-situ conditions [2], [3]. This option is particularly interesting for nuclear engineers where very often there is no possibility to cut or damage studied sample. In addition, recent publications suggest possibility of calculating stress state of the material based on the Raman band shift [1], [4], [5]. Due to the very small number of valuable, non-destructive and fast measurement techniques, Raman spectroscopy is becoming more and more interesting tool, to fill the created gap of lack of high temperature structural and mechanical data.

There is a long history of experimental and theoretical studies of properties and phase transformations in ZrO₂. It is commonly believed that zirconium oxide has 3 polymorphs: monoclinic, tetragonal and cubic [6], [7]. In addition, according to Keramidas et al. [8] even amorphous ZrO₂ can be prepared by precipitating zirconium oxychloride with NH₃ (heating causes crystallization to tetragonal and monoclinic phase). Presence of these phases has a crucial influence on the oxidation kinetics of zirconium. For example, it is believed that tetragonal zirconia scale serves as a diffusion barrier, and may limits the rate of oxidation [9], [10]. Additionally, it has been proven that the oxidation process proceeds on the surface of the metallic substrate where the tetragonal phase is being developed [11], [12]. Therefore, one should expect that this region will play a key role in the control of zirconium corrosion. Recent study confirmed that in the proximity of the metal/oxide interface a thin, continuous layer consists purely from tetragonal phase [13] is created. As mentioned before, this thin layer poses innate protective properties and may be responsible for slowing down the corrosion of the fuel element. Some experimental research indicate that tetragonal phase may be stabilized by stress [14], [15], grain size [16], [17] and displacement from stoichiometry in the oxygen sub-lattice [18]. These findings were confirmed by theoretical calculations performed by Milman et al. [19] and Naumenko et al. [20]. According to Milman et al. [19], metastable tetragonal phase appear until 30 GPa pressure, afterwards phase transition to stable cubic structure follows. Therefore, it is of prime importance to study stress in the oxide and its influence on tetragonal phase stabilization in in-situ conditions.

In this study we present effect of high temperature oxidation on the position of selected low frequency Raman bands. The structural and mechanical properties of zirconia developed on pure zirconium and zirconium alloy (Zr–1%Nb) have been studied during constant oxidation at 600 °C. Careful analysis of selected monoclinic Raman bands allowed us to calculate the stress state developed in the oxide during high temperature treatment in both materials. Continuous, individual for each sample Raman band displacements have been registered. Presented results for the first time proved good correlation between zirconia developed on pure zirconium and its alloy. This work is a part of general study concerning the effects of stress on stabilization of sub-oxide phases in zirconium/zirconia systems.

Section snippets

Material preparation

The studied material (pure zirconium with 99.2% purity) was provided as 0.5 mm thick recrystallized sheet by GoodFellow Cambridge Ltd laboratory. The zirconium alloy (Zr–1%Nb) sample comes from an original piece of material planned to be used in the previous design of the nuclear reactor. Addition of niobium (and other elements such as: Fe, Sn, Cr, Ni) improves mechanical and anti-corrosion properties of zirconium. The resulting alloys are commonly termed as zircaloys [13]. Reported in this

Experimental results and discussion

Fig. 2A) presents Raman spectroscopy signal recorded during 6 h of continuous high temperature oxidation at 600 °C under air at normal atmospheric pressure of pure zirconium sample. The first measurement, defined as 0 h, was performed after reaching the temperature of 600 °C and thermal stabilization of the stove for 5 min. Afterwards, the measurements were performed in 1-h intervals for 6 h. During the whole measurement process, a constant temperature was maintained in the furnace. Reported

Conclusions

This work consists in a characterization of zirconia scale developed on pure zirconium and zirconium alloy during high temperature corrosion at 600 °C using Raman spectroscopy technique. Conducted in-situ Raman analysis aims to help understanding phenomena occurring in the external part of the oxide scale. For the first time, based on the Raman band displacement, growing stress has been calculated. Obtained results, indicate that the stress state developed in the course of oxidation process is

Acknowledgements

Financial support from Foundation for Polish Science through the HOMING PLUS/2013-8/7 program is gratefully acknowledged.

References (29)

L. Kurpaska et al.
Spectrochim. Acta Part A Mol. Biomol. Spectrosc.
(2014)
B. Panicaud et al.
Corros. Sci.
(2013)
L. Kurpaska et al.
J. Nucl. Mater.
(2015)
J.K. Dawson et al.
J. Nucl. Mater.
(1968)
M. Tupin et al.
J. Nucl. Mater.
(2003)
B. Benali et al.
Appl. Surf. Sci.
(2006)
W. Qin et al.
Acta Mater.
(2007)
P. Bouvier et al.
J. Phys. Chem. Solids
(2000)
Barberis
J. Nucl. Mater.
(1995)
X. Iltis et al.
J. Nucl. Mater.
(1995)

J.E. Maslar et al.

J. Nucl. Mater.

(2001)

P. Barberis et al.

J. Nucl. Mater.

(1997)

M. Kemdehoundja et al.

Appl. Surf. Sci.

(2010)

N. Pétigny et al.

J. Nucl. Mater.

(2000)

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Shift in low-frequency vibrational spectra measured in-situ at 600 °C by Raman spectroscopy of zirconia developed on pure zirconium and Zr–1%Nb alloy

Highlights

Abstract

Graphical abstract

Introduction

Section snippets

Material preparation

Experimental results and discussion

Conclusions

Acknowledgements

Spectrochim. Acta Part A Mol. Biomol. Spectrosc.

Corros. Sci.

J. Nucl. Mater.

J. Nucl. Mater.

J. Nucl. Mater.

Appl. Surf. Sci.

Acta Mater.

J. Phys. Chem. Solids

J. Nucl. Mater.

J. Nucl. Mater.

J. Nucl. Mater.

J. Nucl. Mater.

Appl. Surf. Sci.

J. Nucl. Mater.