1TPL dismantling project review C. Brosset TORE SUPRA Association EURATOM-CEA 2006/12/08 TPL...

2006/12/08 1TPL dismantling project review C. Brosset

TORE SUPRAAssociationEURATOM-CEA

TPL dismantling project review

D program : analysis for D content, erosion/redeposition and samples management



TORE SUPRA : TOROIDAL PUMP LIMITER

Plasma Facing Components of the limiter

PLANSEE (AMC) CFC

Armour CFC

Heat sinkCopper alloy 6mm

Water Inlet / outlet

TPL 30° sector

48 standard PFC



CFC Tiles of the TPL

z y

x x = 23 mm

x = 28 mm

y = 22 mm

21 tiles, length & width

x

30° sector, 48 fingers

xFibre directions

y

z

y

z



What do we expect in erosion area?y

x

z

- Uniform distribution of D in (x,y) plans except, may be, near the edges of the tiles due to shadowing effects of bordering tiles- Decreasing depth profile in z direction, up to 2, 4, 6mm?- Presence of carbon deposits in the gaps (D concentration <1% NMR and µNRA measurements)- Possible segregation in the rear surface of copper coming from the Cu/CFC interface



What do we expect in carbon deposition area?

- D concentration of 5 up to 10% in the deposited carbon layer (previous results from NMR & µNRA experiments) - Low D concentration in CFC since the deposition area is a self-shadowed area (only radiated flux)

y

xz


TORE SUPRAAssociationEURATOM-CEA Analysis programme (1/2)

•Need to find out the deuterium in all the thickness of the tiles if necessary

Cross-checking of different methods of investigation Method Characteristic Remarks

NRA 2H(3He,p)4He

Ion-beam analysis3He energy 0.7-3 MeV

High selectivity & sensitivityDepth profiling (up to 8-10µm)Need thin films or extrapolation of the D profile to obtain D content Non-destructive but ion-induced detrapping

µNRA2H(3He,p)4He

Beam size ~5x5µm1-3 MeV

Dedicated to D trapping sites investigation (in parallel with local probe like MET/EELS)

SIMSIon sputtering

O2+ (10-15keV)

Qualitative depth profiling of D, C and impurities (H, B, metals)Can be quantitative by NRA cross-checkingDestructive method

TDSThermal desorption

spectroscopyRT<T<~1300°C

Total D content in the bulk of sample Need appropriate sample size fitting the heating system dimensionsDestructive method



D Retention Analyses:•Current collaborations:

– NRA: IPP Garching (J. Roth team, Germany)

– µNRA: Laboratoire Pierre Süe (CEA/DSM/LPS, CEA Saclay, France)

– SIMS: Laboratoire d’Etudes et d’Examens des Combustibles (CEA/DEN/DEC/LE2C/LECA, CEA Cadarache, France)

– TDS: IPP Garching (J. Roth team) MEPhI (L. Begrambekov team, Russia) & DRFC (IPP Group)

•New proposals…


TORE SUPRAAssociationEURATOM-CEA Analysis programme (2/2)

•Mobility and retention of D in CFC are related to the structure of pores and surfaces available inside the material

•CFC structure is suspected to be modified under high heat flux irradiation

irradiated CFC characterization is needed

Method Characteristic Remarks

Adsorption isotherms (*)

Thermodynamical method

Micro, meso, macro-porosity investigation

MET (*), X-ray diffraction Structural method

Structure & texture

investigation

Raman, ATR/FT-IR

Spectroscopic methods

Vibrational structure

C-D bonding investigation

MET/EELS (*) Structural & electron methods

Electron structure (C hybridization

state) C-D bonding investigation

(*) destructivetechnique



CFC Characterization: •Current collaborations:

– Porosity & structure investigations: Laboratoire de Physique des Interactions Ioniques et Moléculaires (PIIM), P. Roubin team (Université de Provence, France)

– Atomic & electron structure: Laboratoire TECSEN, F. Bocquet (Université Paul Cézanne, France) & N. Bernier (DRFC – PhD student)

– Electron microscopy: Centre Pluridisciplinaire de Microscopie & de Micronalyse (CP2M), W. Saikaly (Université Paul Cézanne, France)

•New proposals…



Samples Preparation

Objectives: 1) being able to analyse D-retention related

issues all along the thickness of the tiles2) being able to perform different

complementary experiments on the same tile, even if most of the techniques are destructive

3) being able to work with different groups, in different laboratories, on the same tile samples and at the same time



•The first step will be the cutting of the CFC tiles from the heat sink because the main source of radioactivity is collisions between neutrons (produced during plasma discharges) and impurities contained in the copper alloy of the heat sink.

•Due to this radioactivity, a one month wait is mandatory before doing anything. As soon as we will obtain the official agreement for working on the fingers, we will perform the cutting. The delay could reach 1 to 6 months.

•Since we want to analyze the CFC all along the z direction, we will cut the tiles precisely at the interface between CFC and Copper.

•At least, 4mm thick CFC samples are expected to be obtained. •This operation is expected to be performed at the DRFC.

Samples Preparation


TORE SUPRAAssociationEURATOM-CEA Samples Preparation

I propose to cut the tiles in 4 identical partsSuccessful tests have been performed using a saw equipped with a diamond wire (CP2M)Polishing the surfaces might be necessaryTests are under way

For NRA experiments Analyses can be performed both on the top-surface (taking into account the carbon layer) and on the side (z direction) allowing to study the depth profile in different points (even at low energy)z

Two ~10x10x2mm samples for TDS experiments(typical sample size required for the DRFC device)D content in the first 2mm

thick part of the tileD content in the last 2mm thick part of the tile

For CFC characterization studies

For SIMS analyses

23 to 28mm

22m

m~4mm



Timing

•sector dismantling: May 2007

•CFC tiles available: 1 to 6 months later

•Samples available at the DRFC: ~1 month later

•Samples available for exporting outside the CEA centre: ~2/3 weeks later

•If this forecast is good, we can expect to begin the analysis at the latest in February 2008 and, in the best case, in Sept./Oct. 2007.



Erosion/deposition measurements

•Objective: mapping of the erosion & carbon deposition areas

•Means: confocal microscopy

Scans of 100x100mm

Steps of 0.1mm

z resolution <1µm



Saw equipped with diamond wire



Sepcarb® CFC-N11(Snecma Propulsion Solide, SAFRAN Group)

1TPL dismantling project review C. Brosset TORE SUPRA Association EURATOM-CEA 2006/12/08 TPL...

Documents

Transcript of 1TPL dismantling project review C. Brosset TORE SUPRA Association EURATOM-CEA 2006/12/08 TPL...