Fast Reactor Fuel Fabrication and Characterization

Randall Fielding, Idaho National LaboratoryAFC Advanced Reactor Fuels Lead

Metal Fuel Fabrication

<Hazcat III (<700g U-235) Arc melting (alloy production and

slug casting) < ~40 gram and <~350 gram

Induction melting and casting, up to ~3 kg (U alloys only)

CNC machining (lathe, mill, EDM) for uranium

Extrusion- 120 ton press, 1000°C Salt bath, 5 ton hydraulic draw bench, 4 die swager (U alloys only)

Pressure resistance and GTAW orbital welding in a controlled atmosphere

Heat treatment furnaces Hot/cold rolling mill (U alloys only) Reference material processing

fabrication (large grained or single crystal material)

Hazcat II (>700 g U-235, TRU Arc Melting <~40 g Small scale lathe and mill GTAW orbital welding in a controlled

atmosphere Furnaces

Up to 2000°C

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Ceramic Fuel Fabrication

<Hazcat III (<700 g U-235) Lab-scale synthesis capabilities: direct nitridation of

metal, carbide and silicide production through direct melting

carbide and silicide production through direct melting (~250-350 g scale)

Standard press and sinter technology: ball mills, high energy ball mills, various presses, low temperature (bake out) furnaces, high temperature furnaces (~2000° C), Spark Plasma Sintering

Controlled atmosphere sintering i.e. small amounts of water vapor, vacuum, argon, hydrogen, mixtures, etc.

Centerless grinding Experiment encapsulation

• Pressure resistance and GTAW orbital welding in a controlled atmosphere

Reference material processing fabrication (large grained or single crystal material)

Hazcat II (>700 g U-235, TRU) Lab-scale synthesis capabilities: direct nitridation of

metal, carbide and silicide production through direct melting

Standard press and sinter technology: ball mills, high energy ball mills, various presses, low temperature (bake out) furnaces, high temperature furnaces (~2000° C)

Experiment encapsulation• GTAW orbital welding in a controlled atmosphere

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Fresh Fuel Characterization

Chemical and isotopic analysis• ICP-MS, ICP-AES, TIMS

X-ray diffraction Scanning electron microscopy (SEM)

• EDS, WDX, EBSD Transmission Electron microscope (TEM)

• ChemiSTEM, ASTAR, EELS, Probe Correcter Focus Ion Beam

• Plasma, gallium Electron probe micro-analyzer (EPMA) Atom Probe Tomography Atomic Force Microscope

Differential Scanning Calorimetry Laser Flash Diffusivity Thermogravimetry Dilatometry Melt point Determination Mechanical Properties

• Elevated temperature load frame• Microhardness

Resonant Ultrasound Spectroscopy (RT-300°C) SIMS/Auger Raman spectroscopy Computed tomography

• X-ray, neutron

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Cross Walk From Survey

Needs that we can currently support: Integral testing

• Less recent experience with carbide and nitride but capabilities exist

• Metallic fuels several ongoing irradiation projects

Fabrication development and optimization

Material interaction studies• Cladding/fuel/coolant interaction

– Flowing loops are more difficult

• Fuel material property gaps

Gaps:More facilities to do the work

• Current Hazcat II facilities are TRU focused• Need facilities for engineering fabrication

development (LEU)– Needed for process development as well as

larger integral tests

Irradiation Testing Capability in Support of Fast Reactor Fuels

Nate Oldham, Boone Beausoleil, Gary Povirk, Jason Harp, Nicolas Woolstenhulme, Dan Wachs, Steve HayesIdaho National Laboratory

Andy Nelson, Kory Linton, Kurt Terrani, Chris PetrieOak Ridge National Laboratory

GAIN Integration MeetingMarch 5, 2019Boise, Idaho

DBA

SBOLOCA

RIA

SSAOO

Ramps Trips

Modern Fuel Testing Strategy

Conduct the fuel performance research necessary to develop, understand, optimize, and license advanced nuclear technology

Integral Testing UnderPrototypic Conditions

Separate Effects and Semi-Integral Testing

Thermal Mechanical

µStructural Evolution

RadionuclideTransport

MaterialProperties

TransientTherm-Hyd

M&S

Operating LicenseSimplified tests allow for better

instrumentation and data collection

Integral Testing Irradiation Capability

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Spectrum

Energy Deposition

Temperature

Outer A Position

• Excellent fuel behavior simulation• Limited cladding irradiation damageAdvanced Test Reactor

Fast Reactor Fuel Irradiations in ATR

Key Findings:1) High Pu (30 wt.%)

alloys perform well2) Am, Np additions do

not degrade fuel performance

3) Mo-based fuel alloys not compatible with SS cladding

4) Pd reacted with Zr not available to immobilize Ln FP’s

5) Low smear density fuels geometrically unstable in solid cylindrical geometry

6) Low smear density annular fuels geometrically stable, swelling accommodated by central annulus without cladding strain

U-10ZrAnnular55% SD

4.6% burnup

U-10MoAnnular55% SD

4.6 at% burnup

Semi-Integral/Separate Effects Irradiation Capability

FAST in ATR

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HFIR Mini-FuelSmall I Position

Reduced diameter and increased enrichment allows for accelerating burnup accumulation (30% BU in ~1 yr) with prototypic temperature profile

Na Loop (2022) Heat Sink Capsule (2020)

Transient Testing Irradiation Capability

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Summary

Irradiation testing capability is available to support SFR fuel studies including– Integral fuel testing is currently available at ATR

• Fully integral testing will require a fast spectrum test reactor– Semi-integral and separate effects testing is being established at ATR and HFIR– Transient testing capability will be available in the near future

• A rich library of historically irradiated materials (EBR-II and FFTF) can be recovered from storage for testing

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Neutron Radiographs of 1st TREAT Tests

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PIE and Out-Of-Pile Testing

Jason M. HarpPostirradiation Examination Department – Idaho National Laboratorywith contributions fromKory LintonOak Ridge National Laboratory

GAIN-EPRI-NEI Advanced Fuels WorkshopBoise, ID March 5, 2019

INL Postirradiation Examination Facilities –Engineering Scale

Hot Fuel Examination Facility– Large Ar atmosphere hot-cell– Can accept up to full sized commercial fuel

rods / casks– Existing Standard Exams

• Irradiation Test Disassembly and machining• Visual• Neutron radiography

(thermal, epi-thermal)• Gamma scan (axial, radial isotopic data)• Metrology (dimensional change)• Fission gas release• Optical microscopy• Vickers and Knoop Microhardness• Density• Mechanical testing with furnace• Oxide layer thickness

• Furnace Testing• TRISO FACS Furnace & FGR system• Electrorefining studies• Refabrication - forthcoming

– Ability to add custom equipment for targeted examinations

Analytical Laboratory– Air hot-cells for dissolving irradiated fuel– Chemical Analysis (Burnup)

• Mass Spectrometry• Quantitative Gamma Spectrometry

– Fresh Fuel CharacterizationFuel Conditioning Facility

– Additional Space for targeted exams

ORNL Postirradiation Examination Facilities –Engineering Scale

Irradiated Fuels Examination Laboratory (IFEL) – 3525– U-shaped array of air cells– Glove box and contamination zone areas

available– Additional stand alone shielded cell for more

sensitive set-up of experimental work– Flexible and diverse cask handling– Specimen Preparation and Metallography– Welding Irradiated Cladding– Specialized Equipment

• Advanced Diagnostics and Evaluation Platform (ADEPT) PIE of LWR Fuel Rods including Gamma Scanning, Eddy Current and LVDT Assembly, Rod Puncture, and Gas Sampling

• Severe Accident Test Station (Integral LOCA, Oxidation, and High-Temperature Furnace)

• SEM Adjacent to Cell with Shielded Handling• Irradiated Microsphere Gamma Analyzer (IMGA)• Core Conduction Cooldown Test Facility (CCCTF) for

HTGR – Fission Gas Release and Metallic Fission Product Release Up to 2,000°C

Irradiated Materials Examination and Testing (IMET) – 3025E– Air cells, Low alpha contamination facility (<70

dpm / 100 cm2). – Physical and Mechanical Properties Testing

• High-Temperature Tensile Testing• Fracture Toughness Testing• Laser Profilometry• Instrumented Charpy Impact Machine• Fatigue Testing• Vickers Microhardness Testing

– Optical Examinations• In-Cell SEM, Fractography• Video Equipment, Non-Contact Extensometry Severe Accident Test Station

INL and ORNL Electron Microscopy and Thermophysical Property

Several Facilities exist at INL and ORNL including– Irradiated Materials Characterization

Laboratory (IMCL) {INL}– Electron Microscopy Laboratory (EML)

{INL}– Low Activation Materials Development

and Analysis (LAMDA) Laboratory {ORNL}

Capabilities– Sample Preparation– Microstructural Characterization (IMCL,

EML, LAMDA)• Electron Microscopy, SEM, Dual Beam

(SEM/FIB), Plasma FIB, TEM/STEM (EDS, SAED, EELS)

• EPMA (quantitative microchemistry)

• X-ray Tomography• X-ray Diffraction• Atom Probe Tomography

– Thermophysical Property Measurements (LAMBDA, IMCL)• Density, dilatometry, electrical prop.,

thermal diffusivity, thermogravimetric analysis/DSC, Hydrogen/Oxygen analyzer

• Irradiated Fuel dilatometry, thermal diffusivity, specific heat, position sensitive thermal conductivity

• Low temperature fundamental properties– Mechanical Properties

• Is-situ tensile testing• Nano-indenter testing

– SiC Temperature monitor evaluation

Cross Walk From Survey

Needs that we can currently support:Legacy Data

– Retrieve data from national lab archives– Retrieve historically irradiated fuel for new

PIE and apply new material science tools that were not available historically

Facility Access– Perform PIE on historical samples– Perform PIE on new irradiations

Advise Vendors on known fuel performance issues– Experience from metallic fuel irradiations– Experience from ATF irradiations

Gaps:Specific Testing Needs

– New testing methods require significant funding and engineering time to deploy in the hot-cell

Experience beyond LWR’s and SFR’s– Most equipment is geared towards

SFR or LWR needs– Other reactor concepts may need

different testing infrastructure

DOE Fast Reactor Fuel Performance Assessment Capability

Pavel MedvedevIdaho National Laboratory

Survey results

Do you have the simulation codes/tools needed to analyze your specific fuel design and the required safety/licensing calculations?

– Lightbridge No– EPRI– GA No– Westinghouse Yes– OKLO Yes

Survey confirms industry need for fast reactor fuel performance code– Important for continuing DOE support for BISON

DOE capability (currently under development)

Scientific computing capabilities– Falcon, SGI ICE-X system, 34,992 cores, 121 TB, 1,088 TFlops

Fast reactor fuel performance code (BISON) Features

– Metallic and MOX fuel with SS cladding– Any geometry– Instant addition of new material models– Coupling to other analysis codes

Purpose– Predict cladding failure– Justify and extend peak fuel burnup– Justify and extend peak fuel temperature– Simulate LOCA and RIA – Investigate impact of engineering changes on fuel performance, especially during

transients• Coatings, liners, annular fuel

– Justify fast reactor fuel testing in a thermal spectrum with Cd shrouds – Design better irradiation experiments

Connecting DOE-NE capability with industry

22Chris Stanek NEAMS National Technical Director

BISON information

bison.inl.gov– Bison theory, user guide, assessment, user training

gain.inl.gov/SitePages/Workshops.aspx– GAIN EPRI Modeling and Simulation Workshop Presentations January 24-25, 2017

www.nrc.gov/public-involve/conference-symposia/adv-rx-non-lwr-ws/2017/stanek.pdf– overview of fuel performance modeling (BISON) by NEAMS director