Direkt zum Inhalt
  • Paul Scherrer Institut PSI
  • PSI Research, Labs & User Services

Digital User Office

  • Digital User Office
  • DE
  • EN
  • FR
Paul Scherrer Institut (PSI)
Suche
Paul Scherrer Institut (PSI)

Hauptnavigation

  • Research at PSIÖffnen dieses Hauptmenu Punktes
    • Research Initiatives
    • Ethics and Research integrity
    • Scientific Highlights
    • Scientific Events
    • Scientific Career
    • PSI-FELLOW
    • PSI Data Policy
  • Research Divisions and LabsÖffnen dieses Hauptmenu Punktes
    • Overview
    • Research with Neutrons and Muons
    • Photon Science
    • Energy and Environment
    • Nuclear Energy and Safety
    • Biology and Chemistry
    • Scientific Computing, Theory and Data
    • Large Research Facilities
  • Facilities and InstrumentsÖffnen dieses Hauptmenu Punktes
    • Overview
    • Large Research Facilities
    • Facilities
    • PSI Facility Newsletter
  • PSI User ServicesÖffnen dieses Hauptmenu Punktes
    • User Office
    • Methods at the PSI User Facilities
    • Proposals for beam time
    • Proposal Deadlines
    • Data Analysis Service (PSD)
    • EU support programmes
  • New ProjectsÖffnen dieses Hauptmenu Punktes
    • SLS 2.0
    • IMPACT
  • DE
  • EN
  • FR

Digital User Office (mobile)

  • Digital User Office

Sie befinden sich hier:

  1. PSI Home
  2. Labs & User Services
  3. NES
  4. LNM
  5. Research Programs
  6. Nuclear Fuels
  7. Fuel Burn-Up

Sekundäre Navigation

Laboratory for Nuclear Materials

  • About LNM
  • Events
  • Organisation / People
  • Research Programs Ausgeklappter Submenü Punkt
    • Advanced Nuclear Materials
    • Nuclear Fuels Ausgeklappter Submenü Punkt
      • H-Uptake
      • Cladding Mechanics
      • Fuel Burn-Up
      • Cross-Cut Synchrotron
    • Materials Ageing & Structural Integrity
      • ZINC
      • PLiM
      • PROBAB
      • SAFE
      • DIAGNOSTICS
      • Helium Effects on IASCC
      • PARENT
      • NORA
      • CPFEM
  • Experimental Facilities
    • Hotlab
    • Hydrogenation
    • SINQ Target Irradiation Program (STIP)
    • In-situ Creep under Irradiation Facility
    • Electron Microscopy Facility
    • Metallography
    • Mechanical Testing
    • Corrosion Testing
    • Non-Destructive Characterization
    • Beamline Techniques at SINQ/SLS
  • Teaching and Education
    • List of PhD Theses
    • List of Master Theses
  • Advisory Committee
  • Partners / Links
  • Publications
  • Scientific Highlights

Info message

Dieser Inhalt ist nicht auf Deutsch verfügbar.

Fuel properties changes during burn-up

During fission of the fuel the UO2 pellets change their structural, mechanical, chemical and physical properties. Pushing the fuel to high burn-up is of interest to reduce the amount of highly radioactive spent fuel or waste per produced kWh. The research work concentrates on the changes of the fuel on the basis of this high burn-up, considering its still safe operation. The research work comprises the following aspects: fission products formation and distribution, induced stresses in the fuel and formation of sub-grains, formation of the so-called high burn-up structure, fuel additives or dopants and interaction between fuel pellet and cladding.

Various analytical methods are applied:
  • Photon based – Synchrotron radiation techniques (μXRD, μXRF, μEXAFS, μXANES), γ-scanning, EDX
  • Electron based – Scanning and Transmission Electron Microscopy (E)SEM and TEM, Electron Energy Loss Spectroscopy EELS, Focused Ion Beam FIB, Electron Probe Micro Analyzer EPMA
  • Isotopic analyses – Mass spectrometry (SIMS, LA-ICP-MS)
  • Others – Light optical microscopy, fission gas measurements, Positron Annihilation Spectroscopy (PAS)

Example – TEM for studying the electron energy loss

EEL spectra as recorded for various UO2 thicknesses.
EEL spectra as recorded for various UO2 thicknesses.
Lamellae of UO2 are used to quantitatively analyze the EEL spectra as function of sample thickness. The M, N, O and P edges are recorded from 0 to 4000 eV loss, allowing recon-struction of the electronic transitions. The edge analysis also helps to identify the plasmon peak of the core electron transition. Going through a range of thicknesses (~20 to ~200 nm) the electron mean free path and cross section for inelastic scattering can be derived in the plasmon part of the spectrum.

Example – XAS and fission products

X-ray absorption spectroscopy (XAS) can be used to determine the atomic environment of specific elements, e.g. of fission products. The analysis of volatile krypton in irradiated UO2 has been successfully achieved by XAS. Taking into account that the formation of fission gas bubbles is mainly governed by the production of xenon, and knowing the ratio between xenon and krypton, an estimation of atomic density in the gas bubbles is possible. Further: non-volatile fission products are mostly of interest in respect to their chemical bonds (e.g. metallic fission products).

Example – XRD and fuel structure

With increasing burn-up the fuel grains suffer more and more restructuring, starting with distortion, increasing dislocation densities, forming sub-grains with small-angle boundaries and ending up with fuel polygonization. The restructuring is of interest in case of temperature transients of the fuel which can lead to fuel fragmentation (or, in extreme cases, pulverization). The induced stresses which are presumably the driving force for restructuring can be analyzed with X-ray Diffraction XRD.
Left – distinct X-ray diffraction of an un-irradiated, undisturbed grain; middle – streaking of the diffraction spot induced by grain distortion due to irradiation and embedding of fission products, right – further streaking and formation of sub-spots indicating formation of small-angle grain boundaries.
Left – distinct X-ray diffraction of an un-irradiated, undisturbed grain; middle – streaking of the diffraction spot induced by grain distortion due to irradiation and embedding of fission products, right – further streaking and formation of sub-spots indicating formation of small-angle grain boundaries.

Mit Sidebar

Contact

Dr. Goutam Kuri

Paul Scherrer Institute
OHLA 135
CH-5232 Villigen PSI

Telephone:
+41 56 310 2182
E-mail:
goutam.kuri@psi.ch

top

Fussbereich

Paul Scherrer Institut

Forschungsstrasse 111
5232 Villigen PSI
Schweiz

Telefon: +41 56 310 21 11
Telefax: +41 56 310 21 99

Der Weg zu uns
Kontakt

Besucherzentrum psi forum
Schülerlabor iLab
Zentrum für Protonentherapie
PSI Bildungszentrum
PSI Guest House (in english)
PSI Gastronomie
psi forum-Shop

 

Service & Support

  • Telefonbuch
  • User Office
  • Accelerator Status
  • Publikationen des PSI
  • Lieferanten
  • E-Rechnung
  • Computing
  • Sicherheit

Karriere

  • Arbeiten am PSI
  • Stellenangebote
  • Aus- und Weiterbildung
  • Career Center
  • Berufsbildung
  • PSI Bildungszentrum

Für die Medien

  • Das PSI in Kürze
  • Zahlen und Fakten
  • Mediacorner
  • Medienmitteilungen
  • Social Media

Folgen Sie uns: Twitter (deutsch) LinkedIn Youtube Facebook Instagram Issuu RSS

Footer legal

  • Impressum
  • Nutzungsbedingungen
  • Editoren-Login