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. Li 1,2 , J. Liu 2 , T. Aarholt 2,3 , M. Gass 4 , K. L. Moore 1,5 , M. Preuss 1 and C. Grovenor 2 1 School of Materials, University of Manchester 2 Department of Materials, University of Oxford 3 Department of Physics, University of Oslo 4 Wood plc, Walton House, Warrington 5 Photon Science Institute, University of Manchester

Nanoscale Secondary Ion Mass Spectrometry O - ion source Cs + ion source Sample 1

Materials and Methods: Samples Oxford Initial Oxidation Irradiation Spiked Oxidation Sample Alloy Name Time Oxidation Temp. Temp. (°C) Ion DPA Time (Days) Temp. (°C) Dopant (Days) Medium (°C) 50% 2 H 2 O + 5% Simulated Z4-1 Zircaloy-4 131 350 N/A N/A N/A 40 320 18 O PWR H 2 50% 2 H 2 O + 5% Simulated Z4-2 Zircaloy-4 131 350 H+ 350 0.25 40 320 18 O PWR H 2 Simulated 50% 2 H 2 O + 5% Z4-3 Zircaloy-4 131 350 H+ 350 0.75 40 320 18 O PWR H 2 100% 2 H 2 O Z4-4 Zircaloy-4 30 360 100% H 2 O N/A N/A N/A 31 360 100% 2 H 2 O Z4-5 Zircaloy-4 75 360 100% H 2 O N/A N/A N/A 31 360 ZNb-1 Zr- 1 wt% Nb 15 360 100% H 2 O N/A N/A N/A 31 360 100% 2 H 2 O 100% 2 H 2 O CNL Zr-2.5 B96 185 325 PH=10.5 N/A N/A N/A N/A N/A N/A Nb (LiOD) 100% 2 H 2 O CNL Zr-2.5 B70 192 325 PH=10.5 neutron 325 2 N/A N/A N/A Nb (LiOD) 2

Top Down Analysis & 3D Reconstruction 3

Cross Sectional Analysis And Re-slicing Cs + beam pixels y z x 4

2 H Diffusion In Zirconium Oxide B70 – In Flux 1.0 Normalized intensity Normalized intensity 1.0 B96 – Out 0.8 0.8 Of Flux 0.6 0.6 0.4 0.4 0.2 0.2 0.0 Metal/Oxide 0.0 Interface Metal/Oxide 0.0 0.5 1.0 1.5 2.0 2.5 0.0 0.5 1.0 1.5 2.0 2.5 Distance (  m) Distance (  m) Interface oxide metal oxide metal oxide metal Li, K. et al. 3D-characterization of deuterium distributions in zirconium oxide Secondary Secondary scale using high-resolution SIMS. Appl. Surf. Sci. 464 , 311 – 320 (2019) Electron Electron oxide metal oxide metal 2 H 2 H oxide 5 metal

2 H Diffusion In Zirconium Oxide 1.6 1.6 Normalized intensity Normalized intensity 1.4 1.4 1.0 1.0 0.8 0.8 0.6 0.6 0.4 0.4 0.2 0.2 0.0 0.0 Metal/Oxide Metal/Oxide 0.0 0.5 1.0 1.5 2.0 2.5 0.0 0.5 1.0 1.5 2.0 2.5 Interface Interface oxide oxide metal Secondary metal Electron oxide metal oxide metal 2 H Hydrogen diffusion coefficients for samples Z4-4 (30+31 days) and Z4-5 (75+31 days) 6

2 H Distribution In Zirconium Oxide 2 µm 300 nm 100 nm 2 H 7

Differences in 18 O and 2 H Distribution Oxide Layer Oxide Layer Cross sectional analysis of sample Z4-1 8 (Zy-4, 131+40 days, 0 dpa)

Differences in 18 O and 2 H Distribution Zirconium Oxide Zircaloy-4 SE 18 O/ 16 O 2 H/ 1 H 1% 1% 1 2 1 2 2 H/ 1 H 18 O/ 16 O 0.02% 0.2% Cross sectional analysis of sample Z4-3 (Zy-4, 131+40 days, 0.75 dpa) 9

Differences in 18 O and 2 H Distribution Oxide Layer Zy-4 Metal 18 O/ 16 O 2 H/ 1 H SE 2 µm 2 H/ 1 H 18 O/ 16 O 10

Dynamic Implantation Advantages • Allows for complete mapping of a feature 1 2 3 4 5 (typically able to capture >95% of oxide layer) • Limited only by stage movement accuracy • Same data capture as normal NanoSIMS 6 7 8 9 10 analysis • 100-150 nm lateral resolution • High mass resolution and sensitivity 11 12 13 14 15 • 10-20 nm depth resolution • Up to 7 isotopes simultaneously • Large area analysis allows for statistical 16 17 18 19 20 approach • Data capture only limited by available time 20 µm 21 22 23 24 25 Current Data Sets • Z4-1: 300 µm 40 µm • Z4-2: 1440 µm • Z4-3: 320 µm 11

Large Area Analysis – 2 H in Zircaloy-4 1.0% 18 O 18 O /16 O 0.2% 18 O Secondary Electron 0.75% 2 H 2 H/ 1 H 12 0.02% 2 H

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 oxide, 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. 14

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. 15