New Methodologies for High Resolution Mapping of Lig ight Ele - - PowerPoint PPT Presentation

New Methodologies for High Resolution Mapping of Lig ight Ele lements in in Zir irconium Oxide wit ith SIM IMS

• C. Jones*1, K. Li1,2, J. Liu2, T. Aarholt2,3, M. Gass4, K. L. Moore1,5, M.

Preuss1 and C. Grovenor2

1School of Materials, University of Manchester 2Department of Materials, University of Oxford 3Department of Physics, University of Oslo 4Wood plc, Walton House, Warrington 5Photon Science Institute, University of Manchester

Nanoscale Secondary Ion Mass Spectrometry

O- ion source Cs+ ion source Sample 1

Materials and Methods: Samples Oxford

Sample Name Alloy Initial Oxidation Irradiation Spiked Oxidation Time (Days)

• Temp. (°C)

Oxidation Medium Ion Temp. (°C) DPA Time (Days)

• Temp. (°C)

Dopant Z4-1 Zircaloy-4 131 350 Simulated PWR N/A N/A N/A 40 320 50% 2H2O + 5% H2

18O

Z4-2 Zircaloy-4 131 350 Simulated PWR H+ 350 0.25 40 320 50% 2H2O + 5% H2

18O

Z4-3 Zircaloy-4 131 350 Simulated PWR H+ 350 0.75 40 320 50% 2H2O + 5% H2

18O

Z4-4 Zircaloy-4 30 360 100% H2O N/A N/A N/A 31 360 100% 2H2O Z4-5 Zircaloy-4 75 360 100% H2O N/A N/A N/A 31 360 100% 2H2O ZNb-1 Zr- 1 wt% Nb 15 360 100% H2O N/A N/A N/A 31 360 100% 2H2O B96 CNL Zr-2.5 Nb 185 325 100% 2H2O PH=10.5 (LiOD) N/A N/A N/A N/A N/A N/A B70 CNL Zr-2.5 Nb 192 325 100% 2H2O PH=10.5 (LiOD) neutron 325 2 N/A N/A N/A

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Top Down Analysis & 3D Reconstruction

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Cross Sectional Analysis And Re-slicing

Cs+ beam z x y pixels 4

2H Diffusion In Zirconium Oxide

B96 – Out Of Flux B70 – In Flux

0.0 0.5 1.0 1.5 2.0 2.5 0.0 0.2 0.4 0.6 0.8 1.0

Normalized intensity Distance (m)

Secondary Electron

2H

• xide

metal

• xide

metal

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0.0 0.5 1.0 1.5 2.0 2.5 0.0 0.2 0.4 0.6 0.8 1.0

Normalized intensity Distance (m)

• xide metal
• xide

metal

• xide

metal Secondary Electron

2H

Metal/Oxide Interface Metal/Oxide Interface

• xide

metal Li, K. et al. 3D-characterization of deuterium distributions in zirconium oxide scale using high-resolution SIMS. Appl. Surf. Sci. 464, 311–320 (2019)

2H Diffusion In Zirconium Oxide

0.0 0.5 1.0 1.5 2.0 2.5 0.0 0.2 0.4 0.6 0.8 1.0 1.4 1.6

Normalized intensity

0.0 0.5 1.0 1.5 2.0 2.5 0.0 0.2 0.4 0.6 0.8 1.0 1.4 1.6

Normalized intensity

Hydrogen diffusion coefficients for samples Z4-4 (30+31 days) and Z4-5 (75+31 days) 6

Secondary Electron

2H

• xide

metal

• xide

metal

• xide

metal

• xide

metal Metal/Oxide Interface Metal/Oxide Interface

2H Distribution In Zirconium Oxide

100 nm 300 nm 2 µm

2H

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Differences in 18O and 2H Distribution

Cross sectional analysis of sample Z4-1 (Zy-4, 131+40 days, 0 dpa) 8

Oxide Layer Oxide Layer

Differences in 18O and 2H Distribution

Cross sectional analysis of sample Z4-3 (Zy-4, 131+40 days, 0.75 dpa)

0.2% 0.02%

SE

Zirconium Oxide Zircaloy-4

2H/1H

1%

18O/16O

1%

1 2 1 2

18O/16O 2H/1H

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Differences in 18O and 2H Distribution

Oxide Layer Zy-4 Metal 2 µm

SE

18O/16O 2H/1H 18O/16O 2H/1H

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Dynamic Implantation

Advantages

• Allows for complete mapping of a feature

(typically able to capture >95% of oxide layer)

• Limited only by stage movement accuracy
• Same data capture as normal NanoSIMS

analysis

• 100-150 nm lateral resolution
• High mass resolution and sensitivity
• 10-20 nm depth resolution
• Up to 7 isotopes simultaneously
• Large area analysis allows for statistical

approach

• Data capture only limited by available time

Current Data Sets

• Z4-1: 300 µm
• Z4-2: 1440 µm
• Z4-3: 320 µm

40 µm 20 µm

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25

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Large Area Analysis – 2H in Zircaloy-4

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Secondary Electron

2H/1H 18O/16O

0.2% 18O 1.0% 18O 0.02% 2H 0.75% 2H

Conclusions

• 3D in-depth analysis shows detailed deuterium distributions in the oxide.
• The diffusion coefficients of deuterium in the oxide have been calculated, and are

similar to those reported by previous bulk measurements

• In Zy-4 samples, localised areas of high deuterium intensity were observed in the
• xide, but only very few of these were found in Nb containing samples.
• Neutron-irradiation strongly affects the observed deuterium distribution.
• Oxygen transport through protective oxide appears to be dominated by transport

along cracks and pores whereas hydrogen transport appears to be possibly diffusion limited.

• Newly formed oxide contains very little hydrogen,
• This may be because it is rapidly lost to the infinite sink represented by the bulk α-Zr.
• Dynamic implantation allows for high resolution, large-scale, isotopic and chemical

analysis of light elements for the first time.

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Acknowledgements M4DE M4DE

The Manchester NanoSIMS was funded by UK Research Partnership Investment Funding (UKRPIF) Manchester RPIF Round 2. Some of this work was supported by UK EPSRC grant EP/M017540/1 and Michael Preuss would also like to acknowledge his EPSRC Leadership Fellowship funding EP/I005420/1. This work is part of a larger project, which is funded in part by the Engineering and Physical Sciences Research Council through the Centre for Doctoral Training in Materials for Demanding Environments, grant EP/L01680X/1. We acknowledge the support of The University of Manchester’s Dalton Cumbrian Facility (DCF), a partner in the National Nuclear User Facility, the EPSRC UK National Ion Beam Centre and the Henry Royce Institute. We recognise Samir de Moraes Shubeita, Paul Wady, and Andrew Smith for their assistance during the H+ irradiation. EPSRC grants (EP/K040375/1 and EP/N010868/1) are acknowledged for funding the ‘South of England Analytical Electron Microscope’ and the Zeiss Crossbeam FIB/SEM used in this research. Support for work on active samples was provided by EPSRC grant EP/M018237/1 and access to the Culham MRF.

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