leci - horia hulubei · leci department of nuclear materials nuclear energy ... 11 concrete cells...

LECIDEPARTMENT OF

NUCLEAR MATERIALS

NUCLEAR ENERGY

DIRECTORATE

DIVISION FOR NUCLEAR

ACTIVITIES, SACLAY

NUCLEAR ENERGY DIRECTORATEDIVISION FOR NUCLEAR ACTIVITIES, SACLAY

DEPARTMENT OF NUCLEAR MATERIALS

SUMMARY

THE LECI

04…

MICROSTRUCTURAL

CHARACTERIZATION

12 …

IRRADIATION CAPACITIES IN THE

SURROUNDINGS OF THE LECI

54…

MECHANICAL

CHARACTERIZATION

38 …

HOW TO PERFORM POST

IRRADIATION EXAMINATIONS

AT THE LECI

58…

4CEA NUCLEAR ENERGY DIRECTORATE

THE LECI

…

5CEANUCLEAR ENERGY DIRECTORATE

THE LECI

…

06 … Purpose of the LECI

07 … Historical data

07 … Strategy

08 … I and K shielded cell lines (building 605)

10 … M shielded cell line (building 625)

11 … Authorized materials

LECITHE


THE LECI

…

The Department for Nuclear Materials (DMN) has forits missions:

to contribute, through theoretical and experimentalinvestigations, to the development of knowledge inmaterials science in order to be able to predict the evo-lution of the material physical and mechanical propertiesunder service conditions (irradiation, thermomechanicalsolicitations, influence of the environment,…);

to characterize the properties of the materials used in the nuclear industry in order to determine their per-formance and to be able to predict their life expectancy,in particular via modelling. These materials can be irra-diated or not, and originate from surveillance programs,experimental neutron irradiations or simulated irradia-tions with charged particles;

Purpose of the LECI

The LECI is a “hot” laboratory dedicated mostly to the characterization of irradiated materials. It has,

however, limited activities on fuel, as a back up to the LECA STAR in Cadarache. The LECI belongs to the

Section of Research on Irradiated Materials (Department of Nuclear Materials).

to establish, maintain and make use of the databasesgenerated by these data;

to propose new or optimized materials, satisfying futureservice conditions and extend the life or the competiti-veness of the associated systems ;

to establish constitutive laws and models for the materials in service, incidental, accidental and storageconditions, and contribute to the development of theassociated design codes in order to support the safetyargumentation of utilities and vendors;

to provide expertise on industrial components, in particular to investigate strain or rupture mechanismsand to offer leads for improvement.

The CEA center at Saclay is located a few kilometers southwest of Paris

THE LECI

The CEA Center at Saclay

The center (certified ISO 9001) is one ofthe 9 research sites of the FrenchAtomic Energy Commission (CEA). It is atop-ranking innovation and researchcenter at European level. More than5000 people work in the center. It plays a major role in the regionaleconomic development. The center ismultidisciplinary with activities in fieldssuch as nuclear energy, life sciences,material sciences, climatology andenvironment, technological researchand teaching.


THE LECI

…

Historical data

The Laboratory for Studies on Irradiated Fuel

(LECI) located on the Saclay site of CEA, was

built and started operation in November

1959. It was registered as Nuclear

Installation n°50 (INB 50) on January 8th,

1968.

The LECI regroups 3 lines of shielded cells:

The K line started operation in 1959,

The I line (Isidore) started operation in1970,

The M line started operation in 2005.

Strategy

The LECI was chosen in the mid 90s to regroup the R&D

means on irradiated materials for CEA, while keeping a

limited capacity for fuel examination.

This decision demonstrated the will to optimize the organi-

sation of nuclear installations at CEA, and implied the

closure and decommissioning of two “hot” laboratories, the

High Activity laboratories (LHA) in Saclay, and the LAMA in

Grenoble.

This strategic decision was at the source of the Project for

the equipment of LECI (PELECI) which included two main

parts:

The renovation of existing facilities (cells of I and K lines)in the building 605 in order to conform to the demandsof the safety authorities made in 1995,

The construction of a new line of hot cells in a new building (M line). This extension hosts the experimental

The LECI in the 60s.

capacities previously used at the LHA (closed in 2003) as well as equipment needed for the new R&D demandsat CEA.

Transportation cask for irradiated materialsTN106


THE LECI

…

I and K shielded cell lines (building 605)

The I line regroups 9 shielded cells whose walls are madeof lead casts inside steel casings.

Each of the shielded cells (from I1 to I6) has two remotehandlers, a lead glass window and a lifting device. The I7to I9 cells only have remote handlers (one or two) and alead glass window.

The K line has different types of cells:

11 concrete cells (from K1 to K11),

2 lead cells (K12 and K13),

1 cast iron cell (K14).

All the cells but 2 (K12 and K13) have two remote handlers, a lead glass window and at least one lifting unit.The K12 and K13 cells only have a lead glass window andremote handlers.

The K line possesses 4 cells dedicated to the managementof the installation:

Two shielded cells used for storage of irradiated fuel andmaterials (K5 and K14),

One shielded cell used for conditioning and notably usedfor the evacuation of fuel (K3),

One shielded cell used to characterize, sort and packageradioactive waste before disposal (K10).

Schematics of I and K lines.


THE LECI

…

M shielded cell line (building 625)

The M line regroups 19 shielded cells. Each cell is made of

a stainless steel casing (containment) around which lead

walls are bolted to ensure shielding.

Each of the cells possesses two remote handlers (except

M16 which has only one), a lead glass window and a

lifting unit.

The building 625 also has an area dedicated to surface ana-

lysis which regroups:

A “TEM thin foil” room in which are installed

electrolytic polishing and ion milling equipment inside

glove boxes (the discs to be thinned are sent from the

M line via pneumatic transfer),

A “Raman” room in which a Raman spectrometer is ins-

talled – the laser beam is brought to the M16 cell via

optical fibres,

A “EPMA” room in which elemental composition

(qualitative and quantitative) is determined (the

samples to be examined are sent from the M line via

pneumatic transfer).

The M line possesses 2 cells dedicated to the management

of the installation:

One shielded cell used for interim storage of irradiated

materials (M08),

One shielded cell used for reception and preparation of

samples for surface analysis (M15).

Schematics of M line.


THE LECI

…

Authorized materials

The LECI is authorized to receive irradiated materials of thefollowing kind:

Irradiated structural materials (steel, zirconium alloys,aluminium alloys…),

Absorbing materials from experimental reactors andnuclear power plants (B4C, HfB2…),

Glass matrices for waste storage,

Ceramics and composites,

Graphite,

Polymers.

As for irradiated fuel coming from nuclear power plants,the conditions are the following:

Cooling time of at least 6 months,

Burn up lower than 90 000 MWj/t and a 235U enrichmentlower than 4,95 % for UO2 fuel elements,

Burn up lower than 45 000 MWj/t and a Pu/(U+Pu) ratiolower than 5 % for MOX fuel elements.

The maximum admissible activities (equivalent 60Co) in theshielded cells of building 605 of LECI are the following:

9,1 1014 Bq for the cells K1 to K5 of the K line,

9,1 1011 Bq for the cells K6 to K11 of the K line,

1,2 1011 Bq for the cells K12 et K13 of the K line,

6,4 1013 Bq for the cell K14 of the K line,

1,2 1011 Bq for the cells I4 to I9 of the I line,

5,3 1013 Bq for the cells I1 to I3 of the I line.

Cell K10 used to sort and packageradioactive waste.


THE LECI

…

The quantity of radioactive matter in building 625 of LECI is limited to:

Irradiated materials whose dose rate is at a maximum equivalent to that generated by 1015 Bq of 60Co in cell M08 and1013 Bq of 60Co in all the other cells,

1014 Bq in tritium,

A total mass of irradiated fuel of 20 g maximum.

The characteristics and dimensions of these materials are limited by the dimensions of the casks in which they are transported and of the shielded cells in which the scientific equipment is located.

Schematics of LECI.

Cell M08 used to characterize and store irradiated samples.

Building 605I and K Lines

Building 625M Line


MICROSTRUCTURAL CHARACTERIZATION

…



…

14 … Main roles of the Laboratory

15 … List of Facilities

17 … Corrosion loop

18… Non destructive examinations

20… Gas analysis

21 … Refabrication of shortfuel rods

22… Creep furnaces

23… Conventional machining

24… Welding, cutting

25… Spark erosion machining

26… Optical microscopy

27… Hardness equipment

CHARACTERIZATION

MICROSTRUCTURAL

Microscopy and irradiation

damage studies laboratory

28… Density

29… Scanning electron microscopy

30… Preparation of EPMA and TEMsamples

31… Cold metallography and preparation of thin foils

32… Transmission electron microscopy

33… Electrochemistry

34… Cold thermobalance and autoclaves

35… X-ray diffractometry

36… Raman microscope

37… Electron probe for microanalysisEPMA

37… Nuclear microprobe



…

The main roles of this laboratory are: Metallurgical and physical characterisation of materialsirradiated in PWR reactors or research reactor in order todetermine their behaviour in relation to other departments within DEN.

To study the uniform corrosion behaviour of irradiatedcladding materials,

Machining, preparation of irradiated test pieces orsamples,

Refabrication of short experimental fuel rods for R&Dprogrammes,

To contribute to the study of new equipment (creep furnace, laser welding, nondestructive test bench, TEM,etc.) and their modifications for shielded cells,

To follow-up design, manufacture and interpretation of R&D programmes that mainly make use of experimental irradiations,

To carry out technological monitoring of studies concerning the behaviour of graphite-based materialsunder irradiation in particular to provide support for theselection of materials for high temperature reactors.

This laboratory is part of the “Commissariat à l’Energie Atomique” (CEA). It is located about 20 km southwest of Paris at the Saclay centre, principally in Building 605. Within CEA's organisation it belongs to theNuclear Energy Directorate (DEN), the Nuclear Materials Department (DMN) and the Section for Researchon Irradiated Materials (SEMI).

The laboratory team is composed of 35 persons including engineers, technicians, a secretary, Ph D students,postdocs, trainee engineers.

We are mainly working on metallic materials such assteels, zirconium, aluminium and nickel alloys and we alsomanufacture or examine fuel rods, graphite, composite orceramic materials.

Our main test facilities are listed after and a dedicatedsheet describes each facility in more details.

The laboratory has more than 30 years experience.

Failure aspect of a spalled zirconium oxide.

MICROSCOPY AND IRRADIATIONDAMAGE STUDIES LABORATORY



…

List of Facilities LECI - INB 50 (1/2)

Facilities of the Laboratory are distributed in the three lines of cells of the LECI, K line, I line, M line and in the

northern zone of the LECI. Some facilities are based in other buildings at the center of Saclay.

The K line includes 13 shielded cells.

Walls are made out of baryted concrete of 1 meter thickness. The

cells have a significant size (3x3x4 m3). This line was renovated bet-

ween 1996 and 2006. Each renovated cell was decontaminated and

equipped with new test facilities.

K Line.

The I Line includes 9 shielded cells.

The cells are of a size smaller than in K line (2x2x3 m3). The cells

consist of lead walls (25 cm thickness), of windows and manipulator

arms. The line was partly renovated in 1997-1998.

I Line.

The M line includes cells put

in active zone in 2005,

and a zone intended for

material surface analysis.

M Line.

The laboratory includes a zone equipped with glove boxes intended

to receive pieces with low activity.

Medium activity zone.

Cell I1 > Radiography bench.

> Laser welding.

> Nondestructive Test Bench for short rods.

Cell I2 > SEM sample preparation.

Cell I3 > Refabrication of short fuel rods/machining.

Cell I4 > Hydrogen content and density measurement.

Cell I5 > Periscope, sample preparation for microprobe

and thin foils.

Cell I6, I7, I8 > Optical microscopy, microhardness and hardness.



…

List of Facilities (2/2)

I Line/Leci.

Cell K1 > Corrosion loop under light water reactors (LWR) conditions, 3 autoclaves.

Cell K2 > Nondestructive test bench for rods (diametral metrology, zirconia, Eddy currents, Gamma spectro-

scopy) and rod puncture (fission gas analysis).

Cell K4 > Sample preparation, machining.

Cell K6 > Pressurisation of samples, creep tests and storage.

Cell K7 > Plunge spark erosion machining.

Cell K9 > Refabrication of short fuel rods, TIG welding.

K Line/Leci.

> SEM.

> X-ray diffractometry.

LAM Room 53/Leci.

> TEM on irradiated

samples.

Building 453. Building 455.

> Electronic microprobe,

RAMAN microscopy,

gloves box lines for the

preparation of thin foils.

> Cell M06 : Wire electro-

discharge machining.

M Line/Leci.> Cold electrochemistry.

> 9-litre high-pressure, high-temperature

autoclave.

> SEM and optical microscope (cold).

> TEM.

> Metallurgy lab and preparation of thin foils.

> Cold corrosion lab

(thermobalance,

autoclaves).

North area/Leci.



…

Corrosion loop, LWR conditions

Performance of corrosion testing in re-circulationautoclaves

Autoclaves

3 autoclaves of 3 liters.

6 autoclave tops:

- 3 “standard” tops allowing the measurement of pressure (bar), temperature (°C), and partialpressure (H2),

- 1 “electrochemistry” top: same as standard topwith 2 electrochemical measurement (4 electrodeseach).

- 1 “slowstrain rate tensile test/creep” top: same asstandard top with 1 traction axis + 1 electrochemi-cal measurement.

- 1 “IASCC crack growth rate measurement” top:same as standard cover with 1 electrochemicalmeasurement (4 electrodes) 1 traction axis + 1 current inlet (2 wires).

Conditions of loop operation

PWR: 360°C, 200 bars, Li, B, H2.

BWR: 360°C, 200 bars, O2 (200 ppb max).

Flow: 40 litres/hour max (10 litres/hour in each auto-clave).

Online chemical measurements: H2, O2, conductivity.

Tensile machine: slow strain rate tensiletest/creep/constant load

Maximum load: 50 kN.

Tensile test minimum speed: 2.7.10-10 m.s-1.

Conditions of static autoclave operation:

Water/vapour: 360°C, 187 bars.

Vapour: 415°C, 100 bars.

Other equipment:

Central gas supply (located outside the building): N2,Ar/He, O2, H2. Preparation, mixing and effluent tanks(x2). Pumps. Heaters/Chillers for loop water. Coolingsystem for autoclave feedthroughs. Resin and filter lines.

Control and safety

The installation is controlled automatically via a PC located in the front area. All components (valve positions), measurements, are transmitted to this controlunit which also handles installation safety.

Corrosion loop in K1 cell.

Bench of non destructive examinations for reprocessed short fuel rods. This bench makesit possible to carry out diameter metrologies along several generators, thickness of oxidemeasurments as well as the control of health of clads.



…

Non destructive examinations

Short fuel rods

Rod length < 800 mm, ø max 9.5mm.

Metrology, Zirconia thickness (step of 0.8 mm, 8 generators).

Eddy currents (circling or ponctual probes; frequency100 kHz to 400 kHz).

Long fuel rods

Vertical rig for 4-m rods: Renault Automation refurbished in 1995 for handling short rods < 700 mm, ø. Max 9.5 mm.

3 interchangeable measurement heads.

Vertical rod movement.

Rod allowing measurements every 22°5 (i.e., 8 diameters).

Metrology- LVDT differential inductance sensor.- 2x2 measurement head with transducers set at 90°.- Static measurements every 0.8 mm.

Non destructive test benches

Zirconia thickness- Spot sensor for Eddy currents: FISCHER.- Static measurements every 0.8 mm.

Integrity cladding- Eddy currents wrap-circling probe (250Hz).- Scan speed 700 mm/min.- Location and characterisation of internal or external

defects.

K2 cell: Diametral metrology bench on right-hand side;puncturing bench of fuel rods on the left.



…

Volume limit: ø.25 mm x h 65 mm.

Germanium sensor and CANBERRA measurement chain.

Low activity limit (1.107 Bq/g) due to diode saturation.

X-ray generator, 420 kVolts (MULLER MG 420S)

Radiography of metal parts (all parts of the type Fabrice fuelrods) for verification of welding,material health defect and/orpunctured hole on fuel rod.

Radiography bench

Gamma spectrometry bench

2 magnifications: x 2 and x 9.

1 binocular head equipped with a 4’’x 5’’ Polaroid photo output and a videooutput with tri-CCD colour camera.

Rotation of vertical arm by ± 45°.

XYZ sample table:

100 x 100 x 100 mm.

SIS control and acquisition system.

Periscope OPTIQUE PETER

X-ray generatorbench in I1 cell.

Radiography of fuel rods (welding zone or fissile column),

of TIG or laser welding for control of the absence of defects (blisters…).

The laboratory is in charge of preparation of irradiationsin the OSIRIS reactor.

Opposite an x-ray of a container intendedfor an irradiation in the OSIRIS

reactor. The Laboratory machined varioussamples taken in irradiated materials,

and reconditioned them. The container was closed by laser welding after pressurization with

1 bar He. Samples will be be reirradiated in the OSIRIS reactor.

Periscope in I5 cell forvisual exams.

Glove box for hydrogen measurement

The gas obtained by

high fréquency heating

is collected by pumping

in a glass bulb placed

in a glove box. Then

the gas is analyzed by

chromatography or

mass spectrometry.



…

Gas analysis

We use induction heating to provide gas release withvacuum installation system. The hydrogen pick-up amountis then determined by mass spectrometry analysis in ano-ther laboratory.

High-frequency furnace: CELES 50 KW

Oven control by potentiometer driven by Cr-Al typethermocouple for a temperature < 1000°C and by aW-Re type thermocouple backed up by an optical pyrometer for a temperature > 1000°C.

Tungsten crucible able to hold parts of max size ø 10 mm x h 15 mm.

Min 500°C Max 2500°C.

Turbo pump: ALCATEL.

Optical pyrometer: IRCON.

Mercury pump: TOEPPLER.

Measurement of hydrogen content

Fission gas release system puncturing (direct determinationof rod internal pressure, free volume); Then, isotopic analyses of Kr and Xe are performed by mass spectrometryanalysis in another laboratory.

Puncture bench

Vertical load equipment for fuel rod.

Fuel rod ø 9.5 mm h. 4000 mm (max).

Puncturing of cladding.

Measurement of free volume (reference volume 300 cm3).

Sampling of fission gases.

Determination of internal rod pressure.

Analysis of fission gases

Glove box for fission gas analysis.

High-frequency furnace for measuring H2 or He content

in I4 cell.



…

Refabrication of short fuel rodsPressurisation of samples

Machining

Horizontal lathe: MJ480A

Machining of parts max 250 mm ø 10 mm (Fabrice design rod diameter,or change of clamp min ø min 4 mm to 14 mm).

Drilling and cutting of small diameter parts, diamond coated drill.

Saw.

Sawing: min. ø 4 mm to 60 mm.

Refabrication of short fuel rods

End plugs cap welding

TIG welder: Centaur III 150P Tw1.

Rotation welding up to Ø 15 mm (Fabrice design rod).

Tack welding.

Seal welding in vacuum: MORANE

Seal welding < 40 bar, Argon, Hélium.

Pressure controlled by electronic manometer.

Drilling lathe in I3 cell for refabricationof "FABRICE" fuel rods.

Diamond cutting in I3 cellfor fuel rods.

Welding machine and seal weldingmachine in K9 cell.

LECI equipment

The LECI has all the equipment necessary for

refabrication of "FABRICE" short fuel rods : cutting

machine, drilling, radiography X, TIG and laser

welding, pressurization, engraving machine, leak

test He, diameter metrology, thickness of oxide,

health of the clad control. These refabricated fuel

rods are intended for ramp tests in experimental

reactor.

Sealing test: ALCATEL ASM100 TURBO CL (helium detection).

Verification of sealing of “FABRICE” rods



…

Creep furnaces

Seal welding up to 200 bars: argon,helium.

ø 15 mm max. Max. length 800 mm.

With cold bench for parameter settings.

KELLER pressure transducers.

Use of a LASERMIKE bench in I1cell.

Cladding laser metrology

Cladding pressurisation benches

5 furnaces < 550°C.

Under primary vacuum, argonpurge possible.

6 measurement zones per furnace.

3 type-K “glove finger” thermo-couples.

Creep furnacesCell K6

The K6 cell contains a bench of pressurisation(200 bars) and 5 creep furnaces ; these furnacesare used for the studies of long duration storage

of fuel materials. After drilling, fuel clad tubesare provided with welded plug and pressurised,

then introduced into the different creep furnaces.A metrology laser bench makes it possible to

measure the deformation of the clads.

Pressurisation bell up to 200 bars in K6 cell.

The cylindrical test-tube is placedunder the TIG welding torch. The tube plug is provided with ahole of 0.7 mm diameter.

Cold pressurisation bench,identical to the bench

established in cell.



…

Conventional machining

Milling machine: EMCO PC mill 50

Travel 200 x 200 x 125 mm.

Consumables: grease, oil, argon, milling cutter allmodels, clips, milling cutter holders.

Verification of parts by MITUTOYO micrometer, digital+ mechanical callipers and laser.

Calibration with each new part using a micrometergauge (BIG DAISHOWA Point master).

Control by EMCO software.

Lathe: EMCO

Travel 170 x 60 mm.

ø. 20 mm max in the pin.

Consumables: grease, oil, argon, tools.

Verification of parts by MITUTOYO micrometer, digital+ mechanical callipers and laser.

Control by EMCO software.

and test pieces made from irradiated materials

Digitally-controlled machining of samples

Engraver: MECAGRAV.

Saw

Saw with diamond disc.

KASTO saw

Cutting of parts max 150 m x 150 mm.

Visual examination using EXAVISION colour camera.

Dimensional measurements (laser).

Installation of a numericallycontrolled millingmachine, nuclearisedin K4 cell.

Samples for mechanical testsproduced at theLaboratory in hotcell.

Installation of a numerical control nuclearisedlathe in K4 Cell .

Stroke sensor ends changed toinductive sensors, Optic dividing-

wheels changed to magneticwheels, Electric wiring changed,Electronic cards /numeric drive

disconnected from machines,Machining area is confined,

Lathe tools capstan-head can bedisconnected to change tools.

All the equipment is adapted for remote handlers use; optical pieces, plastic elements, electronic cards do not resist

gamma radiation.

TIG and LASERwelded test-

tubes.



…

Welding - Cutting

TIG welding: Centaur III 150P Tw1

Rotation welding up to Ø 15 mm (Fabrice design Rod).

Tack welding.

Laser welding

Source Laser Nd-YAG 400 W with computer control.

Cold section with closed circuit.

A welding platter with cold rotation chuck.

A welding platter with hot rotation chuck (2004).

2 optical fibres.

Application

Welding of rod’s end plugs: Zy, inconel, Steel, etc.

Cutting, puncturing possible.

TIG welding machine in K9 cell.

Laser welding bench in I1 cell.

Test-tube places from therein its chuck before laserwelding in the focal plan.

The YAG 400W laser, its power group, the cooling group as well as the “cold”welding bench are located at approximately 50 m of the hot cell.

An optical fiber makes it possibleto connect the laser to the welding

bench established in the cell. The welding bench located out of

the cell makes it possible to parameterize the laser before

welding on irradiated materials.



…

Spark erosion machining

Spark erosion machining bay

Plunge electro-discharge machining under deionisedwater.

Deionised water production unit: MILIPORE.

Spark erosion machine

Max sample size: 100 mm (L) x 180 mm (w) x 25mm (h).

All types of metal (Zy, steel, inconel, AG3Net, etc.).

De-scaling of oxidised samples using diamond-coated file.

Type of electrodes: sparkal, copper, etc.

by plunge spark erosion machining

Preparation of samples for mechanical testing

Max. sample size: 150 mm3.

All types of metal (Zy, steel, inconel, AG3Net, etc.).

Dielectric medium: deionised water.

Brass/zinc wire.

Digital programming and control.

by wire spark erosion machining

Preparation of samples for mechanical testing

Machining by electroerosion driving of samples intendedfor measurement of density.

Machining benches byelectroerosion were

developed at theLaboratory. They both

work with dielectricdesionised water. This

type of machining doesnot induce mechanical

constraints.

Wire spark erosion machine.

Spark erosion machine in K7 cell.



…

Optical microscopy

Polishing machines

2 polishing machines ø.250 mm able to preparesamples of ø. 100 mm max.

Low-speed saws: BUEHLER

Sample ø. max 20 mm.

Adjustable speed, cutting under water.

Vibrating polishing machine: BUEHLER

Allows polishing of samples ø. max 150 mm.

Adjustable amplitude.

Vacuum coating chamber

Sample embedding in araldite ø. 100 mm max.

Optical microscope: OPTIQUE PETER (based on Olympus)

Magnification: 12.5 – 50 – 100 – 200 – 500- 1000.

Light background, dark background, polarisation,interference contrast.

Vickers and Knoop microhardness (from 0.4 to 400 g).

XY table: 100 mm x 200 mm.

Sample diameter up to 100 mm.

SIS image capture and analysis.

Optical microscopy

Preparation equipment

REICHERT-JUNG lEF3

Metallographic observation.

Magnification 1000 max with camera (x1.2) allowing digital photography (SONY printer).

5 objectives: 5, 10, 20, 50 and 100.

OLYMPUS PM10 AD

Magnification 1000 max.

5 objectives: 5, 10, 20, 50 and 100.

Binocular: Olympus SZX12

Magnification 90 max. (zoom from 0.7 to 9 x).

Cold optical microscopy

Optical microscope and preparation cell.

Facilities in cold area.



…

Hardness equipment

Hardness measurementdevice : EMCO TEST

Vickers + Brinell +Rockwell hardness (from 29.4 to 981 N).

Measurement by imageanalysis.

XY table: 50 mm x 100 mm.

Hardness measurements

Instrumented microhardness ISO 14577

Continuous measurement during a hardness test of the forceapplied and penetration depth of the indentor.

Results: Young modulus, hardness, hardness creep, strength.

Indentations: Vickers, Rockwell, Knoop, Cube Corner.

Instrumented microhardness bench

Instrumented microstripe ISO 1073-3

Continuous measurement of the frictionstrength and sound emission during thestripe. Obtaining the critical loads onthin layers.

Technical specifications

• Range of load > 0.03 – 30 N

• Resolution charges > 0.3 mN

• Maximum depth > 200 μm

• Depth resolution > 0.3 μm

• Motorized displacements > XYZ, ı(Z): 120 x 45 x 30, 360°

• Enlarging video microscopy > 200x, 800x, 2000x, 4000x

• Heating > -20°C à 450°C

• Speed of scratch > 0.4 to 600 mm/mn

Hardness machine in I9 cell.

Hardness measurement device in I8 cell.

Motor driventower

Transfer I6/I8

XY motorizedtable



…

Density

Weighing scales: METLLER AE 163

Max mass: 1000 g.

Embedding Equipment.

All types of sample of maximum weight 180 g.

Max sample size 5 cm x 5 cm x 3 cm (Ø x h x l)(solid samples).

and/or double weighing

Density by immersion (phenyl bromide)

ACCUPYC 1330 1CC Glove Box

Gas flow or under vacuum.

Automatic analysis (99 measurements).

Adjustable measurement pressure.

Any kind of samples (solid, powder, liquid, paste).

Sample volume: 0,1 to 0,9 ml.

Reproducibility > 0,03% of the sample volume.

Density by helium pycnometry

Density determination in I4 cell; weight scale.

Helium pycnometry 1 cm3.



…

Scanning electron microscopy

Precision saw: BUELHER

Sample ø. max 20 mm.

Adjustable speed, cutting under water.

Au-Pd and carbon-coating system

POLARON CA508.

BIO-RAD SC500.

Cold SEM: JEOL JSM 5400

EDX analysis (LINK pentafet) eXL software.

1 backscattered electron detector.

Displacement (X; Y; Z; Tilt; Rotation).

Shielded SEM: JEOL JSM-5400

Displacement (X; Y; Z; Tilt; Rotation) by micro-controlpanel.

Sample diameter ø. 50 mm max.

2 backscattered electron detectors.

ROBINSON detector, Classical diode detector (JEOL).

Digital image acquisition.

SEMAFORE software (JEOL).

WDS analyser (spectrometer).

MIKROSS with PEAK acquisition software.

Scanning electron microscopes

Sample preparation General view of the SEM.

SEM column in hot cell; this SEM isequipped with a WDS analyzer.

SEM in cold area (non irradiatedmaterials).



…

Preparation of EPMA and TEM samples

Polishing machines

2 polishing machines of ø 160 mm able to handlesamples of ø max 50 mm.

Adjustable speed.

Low-speed saw: BUEHLER

Sample ø max 20 mm.

Adjustable speed.

Metallic embedding (Sn-Bi)

Embedding of samples of ø 25 x h 9 mm max.

Each sample is embedded in a mould.

Electron probe for microanalysis - EPMA

Transversal thin foils

Dimpler

Concave mechanical abrasion prior to ion or electro-lytic milling of thin foils.

Samples ø. 3 mm, approx. thickness 150 μm.

Heating plate

Samples attached to «Dimpler» or saw support usingwax.

Ion milling unit: BAL-TEC

Ion milling of thin foils.

Standard thin foils

2 pneumatic punches

Punching of ø 3 mm samples from a 100 μm thickribbon.

1 punch press

Punching of ø 1 mm samples from a 100 μm thickribbon and pressed onto a 3-mm support.

Electrolytic milling unit: STRUERS Tenupol 5

Samples of ø. 3 mm and approx. thickness 100 μm.

Thin foils

Sample preparation for EPMA studies in M14 cell.

Glove box for thin foil machining for TEMexaminations.



…

Cold metallography andpreparation of thin Foils

Saws

STRUERS ACCUTOM-2: precision saw.

BUEHLER ISOMET 1000: precision saw.

Polishing machines

STRUERS (RotoPol 11): automatic polishing.

PRESI (MECAPOL 4B): manual polishing (2 plates).

Hot sample mounting press:STRUERS LaboPress-3

Metallographic embeddingwithout shrinkage.

Cold metallography lab

Transversal foils

Dimpler : EAF MODEL 2000

Performs concave mechanical abrasion on samples to obtainthin foils (pre-thinning stage).

Samples of ø 3 mm, thickness approx. 150 μm.

Heating plate: Bibby HC502

Wax sample mounting on supports for «Dimpler» or saw.

Standard foils

Electrolytic milling unit: STRUERS Tenupol 3

Pneumatic punch

Punching of ø 3 mm samples from a 150 μm thick ribbon.

Samples of ø 3 mm, thickness approx. 150 μm.

Thin foils preparation

Dimpler (mechanical abrasion) and electrolytic millingunit for thin foils machining in cold area.

The same equipmentis implanted in a glove

box for thin foilpreparation on

irradiated materials.



…

Transmission electron microscopy

FEI Tecnai 30 G2 microscope, acceleration voltage 300 kVequipped with a STEM system (Scanning TransmissionElectron Microscopy) + EDX analyser (EDAX).

CCD GATAN camera (screen display of TEM, STEM andcartography images + printout).

HT pole pieces (High Tilt).

Sample diameter: 3 mm.

Sample holder: simple tilt, double tilt, double tilt for analysis.

TEM, north area

Transmission electron microscope for irradiated materials studies.

Basal strain canals in irradiated Zy-4 (dose : 0.6 1025 nm-2, i.e. ~1dpa).

Observation of irradiated materials.

JEOL 1200EX, 120kV, transmission electron microscopeequipped with a STEM + EDX analysis system (LINK ISISOXFORD).

Sample diameter: 3 mm.

Sample holder: Beryllium simple tilt, double tilt, doubletilt for analysis.

TEM, Building 453



…

Cold electrochemistry

Measurement of the thickness of zirconia of differentdensities.

Acquisition system

Computer equipped with an acquisition and treat-ment card GAMRY for electrochemical measure-ments.

PH-meter

METERLAB PHM210.

Conductivity meter

METERLAB CDM210.

Measurement cell

Cell feed by WATSON MARLOW 205S micro-pumpequipped with 8 heads.

Counter-electrode in Zircaloy (CEZUS).

Sample holder screw (ø 10 mm stainless steel).

Reference electrode in saturated mercury sulphate(TACUSSEL).

Impedance spectroscopy

RADIOMETER PHM82 potentiometer PH-meter.

Diluted acid, base and buffer solutions.

Acid: sulphuric acid, concentration 10-2 to 10-5.

Base: potassium oxide, concentration 10-1 to 10-3.

Buffer: composed from boric acid and potash or lithine in a K2SO4 support solution of about 10-2.

Acquisition system

Computer equipped with an acquisition and treatment card GAMRY for electrochemical measurements.

Autoclave: SPG

9-litre volume equipped with 3 cooled sample holdermanifolds cooled by a LAUDA RM20 cryostat.

Operating temperature 360°C at 200 bars.

Pressure measurement by SPG M115 control manometer with limiting safety device.

Measurement of hydrogen pressure.

High-pressure, high-temperature autoclave

Impedance spectroscopy.

High temperature autoclave based in cold area.



…

Cold thermobalance and autoclaves

Thermobalance: RubothermMagnetic suspension measurement system: measurement cell in inconel 601JULABO thermostatsPmax = 150 bars,Tmax = 500°C.Zone heated by oven: 200 mm for a tube diameter ofaround 30 mm.

Autoclave 1l: steam generator for thermobalanceRupture disc calibrated to 220 barsPmax = 220 bars,Tmax = 500°C.

Operating conditions: Study medium: gasH2O, H2O/Ar/H2, H2O/Ar/O2, Ar/O2.

High-pressure, high-temperature thermobalance

3 0.5l autoclaves: Rupture disc calibrated to 220 barsStudy medium:

Liquidpure H2O PWR conditions (LiOH(2ppm)/H3BO3(1000ppm))Gaseous atmosphere: Ar/H2, Ar/O2, ArPmax = 220 bars,Tmax = 450°C.Working height: 100 mm, internal ø 80 mm.

1 4l autoclave: Rupture disc calibrated to 220 barsStudy medium: gaseous phaseH2O/Ar/H2, H2O/Ar/O2, H2O/Ar.Pmax = 220 bars,Tmax = 450°C.Working height: 550 mm, internal ø 100 mm.

High-pressure, high-temperature autoclaves

High temperature thermobalance based in cold area.

Autoclave based in coldarea for electrochemistrystudies.



…

X-ray diffractometry

Shielded SIEMENS D500 diffractometer

Cu anticathode.

Rear monochromator.

Shielded scintillation counter.

SOCABIM acquisition and processing software.

Beam cross-section: a few mm2

Microstructural characterisation

Qualitative analysis.

Calculation of cell parameters.

Structure refinement.

Type of samples:

All types, solid or powder (fuel, metals, etc.).

Sample size: (for solid samples)

Minimum 15 mm x 10 mm x 0.5 mm.

Maximum 50 mm x 50 mm x 10 mm.

X-ray difractometer in hot cell.



…

RAMAN microscopy

Triple monochromator.

Confocal system.

Cold part: OLYMPUS BX40 microscope.

Hot part: Nuclear-prepared OLYMPUS BX50 microscoperemote installation in M16 cell (fibre-optic link).

Analysed volume: 1 μm3

Beam cross-section: 1 μm2 (objective x 100)

JOBIN-YVON T64000 spectrometer (M line)

SPECTRA PHYSICS laser, 4 Watt

Qualitative analysis.

Imaging.

All types (ceramic, fuel, glass, corrosion layers) exceptmetals.

Cold side: height 10 mm max.

Hot side: maximum Ø 50 mm x 10 mm.

Sample size

Type of samples

Microstructural characterisation

Raman microscope, laser and monochromatorbased in cold area.

Raman microscope in M16 cell; microscope andlaser are connected by optical fiber.



…

Electron Probe for MicroAnalysis - EPMA

4 WDS spectrometers.

XMAS software (from SAM’X).

Qualitative analysis (spot or imaging).

Quantitative analysis (spot, line scan or imaging).

Elemental characterisation

Analysed volume: a few μm3

Beam cross-section: 1 μm2

Shielded CAMECA SX50 Electron microprobe

All types, solid: ceramic, fuel, glass, metals.

Embedding and polishing mandatory.

10 mm x 10 mm x 10 mm max.Inner size of the embedding mould coating ø 20 mm (40 mm possible).

Sample size

Types of samples

Electron microprobe in shielded cell.

Nuclear microprobe (near the LECI)Easy access to the nuclear microprobe facility of the PierreSüe laboratory: quantitative mapping of oxygen distribu-tion by NRA (Nuclear reaction analysis) and hydrogen distribution ERDA (Electron recoil detection analysis) in irra-diated materials.


MECHANICAL CHARACTERISATION

…



…

Mechanical Characterisation

40 … General presentation of the mechanical characterisation activities

42 … Dimensional measurements (M02)

43 … Static tensile tests (M03, M05)

44 … Dynamic tensile tests (M04)

45 … Impact tests (M10)

46 … Toughness tests (M09, K8)

47 … Axial creep and relaxation tests (M20)

48 … Pressurised tests on cladding tubes (M21, M23)

49 … Iodine induced stress corrosion cracking tests (M19)

50 … Specific test rig design with CAD

51 … Numerical simulation of specific samples

52 … Material constitutive and damage equation identification

53 … Incorporation of test results in data bank



…

The mechanical characterisation is carried out within the Laboratory for MechanicalBehaviour of Irradiated Materials (LCMI).This activity includes mechanical tests on irradiated mate-rials, numerical simulation, material constitutive equationidentification and also comprehension of behaviour anddamage processes. Identified constitutive equations takeinto account different parameters and in particular the irradiation effects. As soon as these relations are identified,they are numerically implemented and provided asmodules linkable with finite elements codes. This processallows a quick implementation and a fast application avai-lability of the acquired test data for numerical simulation.An incorporation of the test data results in the data bank isalso under operation for capitalisation of test results.

The laboratory staff is composed of about 25 permanentstaff (14 research engineers, 10 technicians and 1 secreta-ry) and also 2 to 4 Ph. D. students and some students.

Within LECI, the laboratory is mainly implanted in M Lineand is in charge of mechanical tests on non fissile materials which either come from experimental reactorssuch as the Osiris reactor located in Saclay, or come fromoperating nuclear power plants. We are mainly workingwithin a French frame called “Accords de Collaboration”with EdF, AREVA-NP & NC, IRSN, Defence. Nevertheless, theinternational collaborative and contract parts are increasingand we have contracts with EPRI, EU, Russia and otherorganisations or states.

Selecting a particular samplein the storage cell M08.

A telemanipulator from the insideof a cell.

General presentation of the mechanicalcharacterisation activities



…

The maximum allowed activity within lead cells is in gene-ral near 1013 Bq in term of equivalent 60Co for most of thehot cells in M Line. Due to the recent commissioning of thisnew M Line, dating from October 19th 2005, the laboratory has very recent apparatus and testing machinesdating from 2004. Nevertheless, the acquired experience ismuch wider and most of the technicians have 20 to 30 years experience. They also have participated in thedesign and development of this new M Line and of the tes-ting machines.

Materials currently tested are mainly metallic alloys usedin industrial and experimental reactors: vessel steels, internal stainless steels, austeno-ferritic steels, zirconiumalloys, aluminium alloys. We are also testing other materials such as graphite for UNGG reactors dismantlingand in the near future for the Generation IV. Some developments are also on-going for tests on non fissileceramic and composite materials.

Installation of a pull rod for a calibration operation.

View from inside the axialcreep lead cell (M20).

Front of the creep by internal pressure cell, the operator adjusts the position of diametricalextensometers.



…

Dimensional measurements (M02)

Dimensional measurements are currently performed in thelaboratory, in particular to measure the specimen sectionand by doing so derive the stress from the measurementof load or pressure. Nevertheless, we also have developedsome very precise metrology measurement tools in orderto carry out irradiation growth, swelling or creep measure-ments. For this purpose, the samples are mechanically loaded (e.g. pressurised tubes or flat coupon under

bending), sent to an experimental reactor (Osiris), measu-red out of the reactor in our hot laboratory and then theygo back to the reactor and so on during irradiation. Theseround trips are done until the target neutron dose is rea-ched and with adequate measurement periods in order todetermine properly the irradiation creep kinetics. A similarprocedure is applied for irradiation growth or swelling.

M02 hot cell is a double one (two shielding windows)which contains many precise metrology devices.

Optical macroscopic rig (Optique Peter)

This optical system is devoted to the measurement of

necking at fracture on broken tensile specimens and

crack propagation on broken toughness specimens,

or all other optical measurement. The second picture

is an example of broken cylindrical tensile specimen.

Optical shadow measu-rement system(Hommel)

This optical system operating

in ultraviolet is used for

dimensional checking of the

machining performed in hot

cells. But, this system also

allows precise measurements

for irradiation growth or creep.

Laser scanning system (Z-Mike)

Profile measurements for revolution samples or for ben-

ded slabs for relaxation under irradiation quantification.

Application example in the frame ofdry storage studies

Diametrical profiles on irradiated 4 cycles Zircaloy-4

loaded by internal gas pressure and submitted to

thermal creep.

Cote (mm)

Dia

mèt

re e

xter

ne (

mm

)



…

Static tensile tests (M03, M05)

Tensile tests are the most often requested by customersand therefore the most practiced. In order to fulfil thisdemand, we have 3 tensile/compression testing machineswith bearing capacity and possibilities that are different.The first two presented here are electro-mechanical tensi-le machines. The third one is an hydraulic dynamic tensileone and is described on the next page.

Maximum stroke displacement of 200 mm,

Load cells: 10 kN and 5 kN,

Speed rate: 500 mm/min down to 0.001 mm/min,

Temperature with two shells furnace system: –150°C to 600°C,

Atmosphere: Air or Argon flow,

Control land Software: INSTRON 8800+, Bluehill,Toughness,

Camera through the furnace with closable window,

Specimen types: Tensile test on small specimens (gaugelength 5 mm), Small Punch Test, Bending tests on pre-cracked Sub-sized Charpy,

The main characteristics are

is located in cell M03.

The first static machine, called Mini Traction,

Maximum stroke displacement of ±100 mm,


Speed rate: 0,5 mm/s down to 1 μm/h,

Mechanical axial and diametrical extensometers withceramic rods,

Temperature with two shells furnace system: –150°C to 1000°C,


Control land Software: INSTRON 8800+, Bluehill,


Auto-alignment system for the pull rod (AlignPro),

Specimen Types: Standard Tensile 10-4 to 10-2 s-1 and SlowTensile down to 10-7 s-1.

Its main characteristics are as follows

Tensile, is located in M05.

The second static tensile machine, called Standard

Bending test at room temperature on a subsize Charpytest sample.

View of the standard tensilemachine locatedin the M05 cell.



…

Dynamic tensile tests (M04)

The dynamic tensile machine is hydraulic with an accumu-lator. It is able to achieve tensile tests at intermediatestrain rates in the range of some ten s-1 depending uponthe geometry (L0) of the tested specimen.

The tests achieved on that machine are aiming to coverincidental situations such as RIA or LOCA for the claddingmaterial. In these particular cases, the cladding tempera-ture increases quickly up to high values (900°C) whichnormally under stationary conditions gives rise to irradia-tion defects recovery. But, under the explored transientconditions, the irradiation defects do not have enough timefor recovery and it is very important to know the mecha-nical properties during these transients. In order to avoidthis irradiation defect recovery, the tensile machine in thelead cell M04 is equipped with induction and direct (Joule)heating systems which allow it to achieve heating rates upto five hundred degrees per second. This system is used inparticular for the PROMETRA (TRAnsient MEchanicalPROperties) project which comes in support to CABRI RIAtests performed at Cadarache.

Hydraulic jack with accumulator and maximum strokedisplacement of ±50 mm,


Displacement rate: 500 mm/s down to 0,0015 mm/s,

Axial and diametrical extensometers with ceramic rods,

Temperature with two shells furnace system: 25°C to 1000°C,

Rapid heating rate with induction or direct heating:1200°C at 500°C/s,

Atmosphere: Air,

Control land software: INSTRON 8800+, WaveMaker



Specimen types: standard tensile from 10-4 to 10-2 s-1 andrapid tensile up to 10+2 s-1.

The main characteristics are as follows

This dynamic tensile machine is located in M04 cell.

View of the dynamic tensile machine located inM04.

Induction wires around the cladding ringtensile specimen.



…

Impact tests (M10)

Impact tests (also called Charpy tests) evaluate fractureresistance of materials and also give access to the brittle toductile transition curve. The lead cell M10 includes twopendulum systems with different bearing capacities. Thefirst one is a standard one, with 300 Joule of capacity, isable to test Charpy specimens (in particular 10 x 10 x 55mm). The second one is devoted to smaller specimens (inparticular 3 x 4x 27 mm) called subsize Charpy.

Energy and maximum impact velocity: 300 J and 5.12m/s,

Temperature range: -150°C to +600°C,

Automatic specimen feeding and positioning pneumaticsystem,

are given below

The main characteristics of these impact pendulums

Fully instrumented pendulum system: Load, displace-ment and angle during the impact,

Specimen Types: Charpy-V or U of 10 x 10 x 55 mm orreduced to half thickness,

Energy and maximum impact velocity: 50 J et 3.7 m/s,


Automatic specimen feeding and positioning pneumaticsystem,

Fully instrumented pendulum system: Load, displace-ment and angle during the impact,

Specimen Types: Sub-Size Charpy-V of 3 x 4 x 27 mm or3.3 x 3.3 x 24 mm.

Conventional impact test (300 J)

The operator is preparing the first impact Charpy test

on irradiated material on October 19th 2005 during

the commissioning of M Line.

Example of impact transition curve obtained on subsize impact pendulum 50 Joule for un-irradiated16MND5 pressure vessel steel.

View from the inside of the300 Joule impactpendulum cell.

Impact specimenscurrently tested on300 Joule impactpendulum.

Temperature (C°)

Abs

orbe

d en

ergy

(J)



…

Toughness tests (M09, K8) Toughness tests are used for the determination of thematerial resistance to brittle fracture or ductile tearing. It goes further than impact testing because it gives accessto material characteristics such as KIC and JIC which aredirectly usable in structural integrity evaluations.

The laboratory uses for these tests two hydraulic machinesof different load capacities (100 kN and 250 kN). The toughness specimen type mostly used is CT (CompactTension) as the one shown in the attached photograph. Thespecimens irradiated in reactors are machined and pre-cracked under cold conditions before being irradiated.On the other hand, if an irradiated block is involved, thespecimens must be machined and pre-cracked with thehydraulic machine in the lead cell.

Machine located in M09 cell:

Hydraulic jack with a maximum stroke displacement of± 75 mm,


Displacement rate range: 0,5 mm/s to 1 μm/h,


Axial extensometer with ceramic rods,

Short or long clip gauge for type COD measurement,


Control land Software: INSTRON 8800+, Toughness KIC

and J-da, da/dN, Bluehill,

machines are as follows

The main characteristics of these hydraulic



Specimen Types: CT 10 to CT 25, CTR5 and bending testson pre-cracked Charpy geometry.

Machine located in K8 cell:

Hydraulic jack with a maximum stroke displacement of± 75 mm,


Displacement rate range: 0,5 mm/s to 1 μm/h,


Axial extensometer with ceramic rods,

Short or long clip gauge for type COD measurement,

Atmosphere: Air,

Control and Software: INSTRON 8800+, Toughness KIC

and J-da, da/dN,

Specimen Types: CT 12.5 to CT 50 and structural compo-nents (e.g. lateral buckling of fuel assembly grids).

CT (CompactTension) toughnessspecimen with lateral grooves forJ-da tests.

Broken CT 20 specimen in twoparts by brittle failu-re which is ready forthe measurement offatigue crack length.

View of the inside of cell M09with its cold-hotfurnace and the100 kN loadframe.

CT 50 toughness specimen installed

with a clip gauge inthe cold-hot furnace

on K8 machine.



…

Axial creep and relaxation tests (M20) The creep test is always performed with a load level main-tained constant and by measuring the resulting strain versus time. These tests are quite often achieved for thedetermination of creep limits in order to be able to performstructural dimensioning or guarantee that the structuredoes not undergo any creep strain during operation. Due tothe axial strain instrumentation with extensometer, it isalso possible to perform relaxation test during which strainis maintained constant. By doing so, the stress is decrea-sing with time. This gives information concerning the beha-viour of structural components and the evolution ofstresses in case of imposed strain. There are two creep-relaxation machines in cell M20.

Electro-mechanic jack with a maximum stroke of ± 50 mm,


Displacement rate: 0,5 mm/s down to 1 μm/h,

Temperature range: +50°C to +800°C,

Axial and diametrical extensometers with ceramic rods,


Control and Software: Rubicon system, DMG Creep-Relaxation software,

Specimen Types: Flat or cylindrical tensile specimen,cladding tube.

machines are as follows

The main characteristics of these electromechanical

Mechanical extensometers adapted fortelemanipulation

New extensometers for tensile or creep tests are used

in LECI M Line. They have successfully undergone a

series of tests and modifications. That is a new aspect

in comparison with the old laboratory (LHA) where

tensile tests were performed without extensometer,

only with stroke displacement and compliance correc-

tion. This will improve our measurements.

These mechanical extensometers are able to measure

the axial or diametrical strain on samples during tests

performed as well at high temperatures (up to

1000°C), as well at low temperatures with liquid

nitrogen (-160°C). They are used for uniaxial tensile,

creep and relaxation.

Operating these extensometers with telemanipulators

has required many adaptations from the producer

(Maytec GmbH) and from the laboratory technicians.

In particular, the precise and stable positioning of the

ceramic rods on the specimen was very important. It

was possible only by the use of micrometric plateau

supports for the extensometers. Another important

challenge was to be able to replace the ceramic rods

without damaging the very tiny mechanical system

linked to the LVDT sensor. For this purpose, an alumi-

nium specific tool was designed and machined.

View of thefurnace of axialcreep with axialand diametricalextensometers.



…

Pressurised tests on cladding tubes (M21,M23)

In PWR, BWR or FBR reactors types, the cladding is corres-ponding to the tube containing the fuel pellets. This tube isan important barrier which ensures the function of the firstconfinement wall between the fuel and the primarycoolant. The materials used are zirconium alloys or stain-less steels. The objective of the tests that we are perfor-ming on irradiated claddings is to check the behaviour ofthis material and its evolution with irradiation. The increa-se of fuel burn-up for a better use of fissile material alsoimplies higher neutron doses for the cladding and alsodamage such as oxidation and corrosion which we have toevaluate.

The principle of the tests achieved is to impose an internalpressure on a cladding coupon closed with cap ends whichcan be either Swagelocks or welded end caps. The teststhat we can achieve on these rigs are of different types:burst, creep, relaxation, low cycle fatigue or biaxial.

The second installation, located in cell M23, has four gas (Argon) internal pressurecreep furnaces of up to 1000 bars. The use of a gas allows operation of up to 700°C. This installation is used for creep or relaxation tests.

For this purpose, the laboratory has two installations incells M21 and M23.

The first in M21 is a biaxial machine with oil pressure(max. 2000 bars) where burst, fatigue or biaxial strain flowsurface tests are performed. The axial loading is performedwith a tensile-compression (50 kN) machine which allowsfor control of the cap end effect by compensating or increa-sing it. The use of oil for internal pressurisation limits the maximum test temperature to 400°C.

Biaxial testing machine with oil pressurelocated in M21.

View of two gas internal pressure creep furnacesin cell M23.

Tubular specimenconnected to thepull rod withSwagelock system.

Gas internal pressure creep furnace and its diametrical straininstrumentation.



…

Iodine induced stress corrosion crackingtests (M19) During the operation of pressurised water reactors, eachpower increase induces a significant fuel temperature ele-vation. The low conductivity of the fuel gives rise to a tem-perature gradient which decreases from the fuel pelletcentre towards the outer part, which then conduct to the“Diabolo” shape and an axial cracking of the fuel pellet.The “Diabolo” shape is the origin of an important strain forthe cladding at the inter pellets level. Also, depending onthe fuel burn-up, a more or less important quantity of fis-sile products (Iodine, Cesium) stored in the pellet can bereleased. In this situation, where the fuel pellet behaviourinteracts with the cladding (PCMI - Pellet CladdingMechanical Interaction), the synergic effects of strain andiodine can give rise to iodine induced stress corrosion crac-king (I-SCC).

The system implemented in lead cell M19 is able to achie-ve stress corrosion by internal pressurisation up to 1000bars and temperatures up to 600°C with saturated iodineatmosphere on defuelled irradiated cladding.

Driving on the pressure with the possibility to do com-plex loading including positive or negative ramps andalso plateaux,

Driving on the diametrical strain with the continuousexternal tube diameter laser measurement. This loading mode allows relaxation tests to be achieved,more representative of loading imposed by the fuel tothe cladding during PCMI conditions.

The crack initiation is then observed by SEM (ScanningElectron Microscopy) in order to assess the cracking process.

under two driving modes

The stress-corrosion tests can be performed

View of lead cell M19 from the front area with itsdriving system. View of the driving computer and ofthe scanning laser monitoring.

Tubular specimenwith itsSwagelock andits thermo-couples.

View of iodinestress corrosionsystem in cellM19.

I-SCC machine operating synoptic.

Penn State University (Øe=9.5mm, L=12mm) ring test specimen.



…

Specific system design with CAD

Today, the test assemblies used by the laboratory arebecoming more and more complex. This complexity cancome from the specimen geometry, most often specimenof small dimensions which can maximise the experimentalresults that can be obtained for a given irradiated materialvolume. So, the experimental result quality requires perfectcontrol of the loading and boundary conditions. Theseconstraints require the use of Computer-Aided Design(CAD) tools. For this, the laboratory is equipped with twoworking stations and the CAD software SolidWorks fromthe Cadware company. Out of the improved design for thedifferent elements from test assemblies, it also allows forviewing and optimising the telemanipulability of thedifferent systems in the hot cell. CAD is also used for thedesign of complex systems which often can only then bemachined by electro-discharge techniques.

Test assembly design in orderto pull on the type Penn StateUniversity (PSU) ring.

Test assembly for pulling on PSU ring afterbeing machined.



…

Numerical simulation of specific specimens

The finite element simulation of the tests performed by thelaboratory is an important step sometimes required for abetter interpretation of experimental results.

A better understanding of structural effects which mustbe taken into account when the mechanical behaviourof materials is under study (boundary conditions, modelling of contact with friction, dynamic effects...),

To check the hypotheses made during the test design(stress or strain homogeneity or gradient, results validity in comparison to test standards),

To design and test new systems, which allow a betterrepresentation of loading modes as experimented inreactors (loading biaxiality, multi-functionality samples),

Evolution of the models, specimen geometry or experi-mental test protocols when the match between simula-tion and test is not satisfactory.

The modelling is performed with the finite element codeCAST3M developed by CEA in DM2S/SEMT/LM2S.

calculated results allows

The comparison between experimental and

Comparison between computed hoopstrain(3D simulation with CAST3M) and mea-sured by image correlation.

Friction effects on the load-displacement curvewhen modelling a Penn State University testand comparison with experimental results.

Calculated strain Measured strain

3D mesh of thePenn StateUniversity ring.

Plastic displacement (mm)

Load

(N

)

Penn StateUniversity ringcomputed plasticstrain distribution.



…

Material constitutive equation identifica-tion

The mechanical tests performed under different conditions(temperature, stress…) are grouped as a data bank whichcan then be used for the identification of constitutive equation parameters. These relations and the associatedcoefficients for given test results are then used in finite element simulations allowing for the evaluation of the thermo-mechanical behaviour of structures and in somecases of their damage. The laboratory has also developeda strong competence in this domain and takes charge ofthe numerical implementation of the constitutive equa-tions in software modules which then can be linked to finite element codes. This is, in particular, the case for cladding materials, where the software module MISTRAL®has been developed for many years in the laboratory andis delivered to customers and linked to finite elementcodes such as CAST3M. However, the material coefficientsof a specific material relation are only delivered to theconcerned customer.

Example related to a creep model of stress relievedZircaloy-4 cladding under internal pressure for longterm storage of used fuels:

In order to predict the behaviour of the fuel pin claddingduring storage, a creep strain model was set up based onan experimental results including 103 internal pressurisedcreep tests performed on stress relived Zircaloy-4 old stan-dard, X1 1st phase and AFA-2G, un-irradiated and irradiatedfrom 1 to 5 cycles in PWR within the following ranges:

At temperatures included between 310 and 470°C, For stresses included within 80 to 250 MPa,For time duration less or equal to 208 days for the irradiated material and 666 days for the un-irradiatedmaterial.

This viscoplastic strain model describes well the materialsoftening under the effect of recovery of strain hardeningand irradiation defects. Two material parameter sets associated to two Zircaloy-4 alloys, AFA-2G and X1 1st phaseon one side, old standard on the other side, were identified.

We obtain a very good match between the model and the experiment for the un-irradiated material. The irradiation hardening is well reproduced by the model. The

match between the old and new formulations is quitegood for low strain (<1%), the early creep accelerationobserved on some specimens is much better representedby the new formulation, which nevertheless is not able toreproduce the experimental scatter sometimes significant.

Comparison between the model and the creep testsperformed at 380°C on Zircaloy-4 irradiated 4 cycles.

Time (s)

Hoo

p St

rain

Time (s)

Hoo

p St

rain

Comparison between the model and the creep testsperformed at 470°C on Zircaloy-4 AFA-2G and oldstandard irradiated 4 cycles.

Time (s)

Hoo

p st

rain



…

Incorporation of test results in data banks

Capitalisation of the tests performed on irradiated mate-rials requires the storage of the results and the test condi-tions in data banks. The objective is to archive these expe-rimental data and also to increase the on-line accessibilityfor the laboratory staff but also for project members whohave the adequate rights.

The experimental tests raw files are stored in a shareddirectory which is maintained with regular backup. These

raw files are then treated by Excel Macro in order to per-form test interpretation and extract conventional valuesclassically used for mechanical tests. The same type of pro-cess is used in order to prepare the experimental data forentering in the data bank. In fact, it is necessary to adaptthe data (order modification, unit changes, calculations…)and complete them (e.g. irradiation dose, programmeinformation…) before being able to incorporate those testresults in the data bank. The fact of working with Excelallows the different laboratory members to be able tocontrol the evolutions and modifications of these macros.

Screen used to putin correspondence

the fields betweenthose of a tensiletest and those of

the data bank.


IRRADIATION CAPACITIES IN THE SURROUNDINGS OF THE LECI

…



…

IRRADIATIONCAPACITIES

IN THE SURROUNDINGS

OF THE LECI

The mission assigned to OSIRIS is to per-form technological irradiations, according tothe specifications of customers, to anticipate futuredemands, which will be in the mid-term performed in thefuture Jules Horowitz Reactor (JHR) and to ensure the conti-nuity of programs until the start of the JHR.



…

The LECI performs post irradiation exami-nations for several experimental reactors, propulsionreactors or power plants, but it benefits from the proximi-ty of the OSIRIS reactor in order to carry out R&D programsinvolving experimental irradiations.

OSIRIS is an experimental reactor with athermal power of 70 MW, located on theCEA site of Saclay. It is a light water reactor, open-core pool type, with a principal aim to irradiate undera high flux of neutrons furl elements and structural materials of nuclear power plants. It is also used to produce radioisotopes and doped silicon. The core of thereactor is made up of 38 fuel elements (enrichment of uranium 235 of 19,75%) and 6 control elements.

Loading a sample holder.

Sample holders for an irradiation in the coreof the OSIRIS reactor.



…

An interesting feature of OSIRIS for material irradiations is the high flux offast and thermal neutrons inside the core and inthe periphery, which is higher than that encountered innuclear power plants. OSIRIS is therefore used to study theageing under irradiation of materials and this helps antici-pate the potential problems in nuclear plants. Among theexperiments concerning fuel, some deal with the behaviorunder irradiation of fuel components: fissile material, cladding, fission products… Other reproduce events innuclear plants testing the fuel rods (eg power ramps…).

The core of the OSIRIS reactor can host upto 16 experimental rigs in locations where thefast neutron flux (higher than 1 MeV) is between 1 and 2 1018 n/m2s. Outside the core, 27 rigs can be simulta-neously hosted in the first periphery where the fast flux is10 times lower than in core. Numerous locations are alsoavailable in second and third periphery.

The instrumentation service of OSIRIS designs, builds and manages the techno-logical irradiation rigs and deals with the nuclearstudies associated with the irradiations (neutron, thermaland thermohydraulic calculations, gamma spectrometry,neutronography, dosimetry and nuclear measurements).

Sample holder for fracture toughnessspecimens.


HOW TO PERFORM POST IRRADIATION EXAMINATIONS AT THE LECI

…

EXAMINATIONS

HOW TO PERFORM

POST IRRADIATION

AT THE LECI

YOUR CONTACT

The Nuclear Energy directorate is certified ISO 9001 for the R&Dactivities. Moreover, the LECI belongs to the ISO14001 certification perimeter ofthe center of Saclay.

Service for Studies of Irradiated Materials (SEMI)

AFAQ Certificate.

Commisariat à l’Énergie Atomique - Saclay

Direction de l’Énergie Nucléaire

Direction déléguée aux Activités Nucléaires de Saclay

Point courrier 101

91191 Gif-sur-Yvette - Cedex - France

Telephone: +33 (0)1 69 08 41 17Fax: +33 (0)1 69 08 26 81E-mail: [email protected]

Christ deSaclay

Entrance

Orsay

Gif-sur-Yvette

Paris/Pontde Sèvres

St-Quentin-en-Yvelines

N118

N306

D36

N446

D36


HOW TO COME TO SACLAY?

…

HOW TO COME TO SACLAY?

Via Pont de Sèvres

South/west of Paris (about 40 minutes).

On the west ring road of Paris take the exit: direction Bordeaux/Nantes.

Take the main road 118 direction Chartres/Orléans and take the exit Saclay/Gif surYvette.

At the roundabout of Christ de Saclay take the road D36 direction Chateaufort.

The CEA Saclay is less than a kilometer on the left.

From Porte d’Orléans

South of Paris (about 40 minutes).

On the south ring road of Paris take the A6 highway at Porte d’Orléans and follow the directions: Orléans/Lyon,

then Chartes/Orléans (by highway), then Versailles/Igny- Bièvres-Cité scientifique and then Saclay.

At the roundabout of Christ de Saclay take the road D36 direction Chateaufort.

The CEA Saclay is less than a kilometer on the left.

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COMMISARIAT À L’ENERGIE ATOMIQUE - Saclay

Direction de l’Énergie Nucléaire

Direction déléguée aux Activités Nucléaires de Saclay

Point courrier 101

91191 Gif-sur-Yvette - Cedex - France

Telephone: +33 (0)1 69 08 41 17 - Fax: +33 (0)1 69 08 26 81

leci - horia hulubei · leci department of nuclear materials nuclear energy ... 11 concrete cells...

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