Transcript W coating of CFC tiles for the JET new wall

NILPRP
NATIONAL INSTITUTE FOR LASER, PLASMA AND
RADIATION PHYSICS, BUCHAREST, ROMANIA
W coating of CFC tiles for the JET new wall
- Task Agreement: JW6-TA-EP2-ILC-05
Manufacturing and testing of W-coated CFC tiles for installation
in JET for the ITER-like Wall project
- Task Agreement: JW8-FT-JET-A
Tungsten erosion in the JET divertor
Cristian Ruset, Eduard Grigore
EURATOM-MEdC Association
EURATOM MEdC Association days, Bucharest 26-27 November 2009
OUTLINE
Overview of the Task Agreement: JW6-TA-EP2-ILC-05
“Manufacturing and testing of W-coated CFC tiles for installation
in JET for the ITER-like Wall project”
Current status
Future actions
Conclusions
EURATOM MEdC Association days, Bucharest 26-27 November 2009
The material selection for the ITER ( in particular for the first wall) has a capital
importance on the overall performance of the fusion reactor.
Requirements:
- Good mechanical properties, very good resistance to cyclic high thermal load,
low sputtering yield, low tritium retention, low activation under neutron
irradiation and so on ..
Candidates:
- C (CFC- Carbon fiber composite): disadvantage high tritium retention
- Be: disadvantage low melting point (1555 K)
- W: seems to be a good candidate
EURATOM MEdC Association days, Bucharest 26-27 November 2009
The first option for ITER is a compromise meaning full beryllium main wall
with CFC at the strike points and tungsten divertor baffles and dome. In
order to test this combination including Be, W and W coated CFC tiles, the
ITER like Wall project has been launched at JET (Joint European Torus)
In the R&D phase of the ITER-like Wall (ILW) project (2005-2006) it was
demonstrated that W coatings deposited on CFC by Combined Magnetron
Sputtering and Ion Implantation (CMSII) technology, which was developed in
MEdC Association, had a better thermo-mechanical properties compared
with other coating technologies.
Requirements for the W coatings:
• Thickness 10-15μm
• Impurity content at 5 μm: C less that 10 at.%, O less than 5 at. %
• Cyclic high flux heat resistance: 200 pulses at a power density of 10.5
MW/m2 for 5 s and Thermal screening 26 pulses with power densities from
6.0 MW/m2 to 23.5 MW/m2 and duration from 10 s to 1 s (Tests performed at
Ion beam test facility IPP Garching)
EURATOM MEdC Association days, Bucharest 26-27 November 2009
Structure and chemical composition of the W coatings
W
W
Mo
Concentrations (at.%)
100
Ti
Mo
80
60
40
O
20
0
0
5
10
15
20
25
30
35
40
Depth (at.%)
SEM image of a W/Mo coating
EURATOM MEdC Association days, Bucharest 26-27 November 2009
GDOES depth profile for a W/Mo coating
Cyclic thermal loading test of the coated CFC tiles
SEM surface images of the coating deposited by CMSII (a) and
by conventional magnetron sputtering (b) after cyclic thermal loading
(200 pulses of 10.5 MW/m2 / 5 s)
EURATOM MEdC Association days, Bucharest 26-27 November 2009
Deposition equipment
Image of the deposition equipment
EURATOM MEdC Association days, Bucharest 26-27 November 2009
Interior view of the JET tokamak
Technical specification of the CFC coated tiles:
- Main chamber 10-15μm W coating
- Divertor 200 μm W coating
After testing some prototype tiles coated with 20 μm W by CMSII, a
decision concerning the coating of ~800 divertor tiles by using CMSII has
been made. The task agreement JW6-TA-EP2-ILC-05 was extended.
EURATOM MEdC Association days, Bucharest 26-27 November 2009
Diagnostic covers and shinethrough
protection tiles from the main chamber
coating thickness 10-15 m
Tiles – C from the main chamber
coating thickness 10-15 m
G 4 divertor tiles coated with 10-15 m
W in series production
EURATOM MEdC Association days, Bucharest 26-27 November 2009
G 6 and G7 divertor tiles coated with
20-25 m W in series production
Current status of the W coating production for the JET tiles at 20.11.2009
Status of coating divertor tiles
• Divertor G3 tiles – 49 tiles (100%)
• Divertor G4 tiles – 103 tiles (100%)
• Divertor HFGC tiles – 102 tiles (100%)
• Divertor G6-102 tiles (100%)
• Divertor G7-52 tiles 20 µm (97%)
• Divertor Mushroom tiles - 6 tiles (Ready to be delivered to JET) (100%)
• Divertor G1 - 106 tiles 20 µm (Ready to be delivered to JET) (100%)
• Divertor G8 -105 tiles 20 µm (Ready to be delivered to JET) (100%)
• LBSRP 4 of 106 tiles 20 µm (4%)
Total divertor coated tiles 629 (85%)
EURATOM MEdC Association days, Bucharest 26-27 November 2009
Status of coating main chamber tiles
• Inner Wall Cladding – 70 tiles (100%)
• Shinethrough Protection – 54 tiles (51%)
• Restrained Ring Protection – 57 tiles (100%)
• LBSRP Protection – 93 tiles (100%)
• IWGL (Be) – 68 tiles (100%)
• Diagnostic covers – 64 tiles (79%)
• Divertor B tiles – 80 tiles (95%) (Ready to be delivered to JET)
• Divertor C tiles-104 tiles (100%) (Ready to be delivered to JET)
• Saddle coil 2 tiles ( 11%)
• Poloidal limiters ( 9 tiles; uncoated)
Total main chamber coated tiles 572
All prototypes and ~ 12% of tiles have passed the HHFT (High Heat Flux Tests)
performed at IPP Garching
EURATOM MEdC Association days, Bucharest 26-27 November 2009
According to ITER Like Wall Project Management plan (JW6-PM-EP2-ILC05) (Annex 1) milestones for the year 2009:
Delivery to JET of 25% of the 10 µm main chamber tiles and 25% of the
divertor W-coated CFC tiles
Due date: 30.06.09. Status: Done
Production coating of the second batch comprising 50% of the divertor tiles
Due date: 31.12.09. Status: Done
Future actions:
Production coating of all the remaining tiles
Due date: 30.09.10
Final report and outstanding documentation
Due date: 14.12.10
EURATOM MEdC Association days, Bucharest 26-27 November 2009
Marker tiles for erosion measurements (Tungsten erosion in the
JET divertor TA JW8-FT-JET-A)
A number of markers (a multilayered structure W/Mo/W/Mo) will be used for
measurements of wall erosion
Tiles type used as markers: G1, G8, G6, G7 (4 each type)
Required coating structure: Mo (first layer): 2-3 µm; W (first layer): 12-14 µm;
Mo (second layer); 3-4 µm; W (second layer): 3-4 µm
The markers were already coated and sent to IPP Garching
EURATOM MEdC Association days, Bucharest 26-27 November 2009
W
Concentrations (at. %)
100
Ti
Mo
80
60
40
O
20
0
0
5
10
15
20
25
30
35
Depth (m)
GDOES depth profile for a W/Mo coating
EURATOM MEdC Association days, Bucharest 26-27 November 2009
SEM image for a W/Mo structure
CONCLUSIONS
Up now ~ 85% (629 tiles) of the divertor have been coated. 408 tiles
have been sent already to JET and 221 are ready to be delivered.
274 tiles from main chamber have been delivered to JET, and 318 are
ready to be delivery.
Results of the HHF test at IPP
- tested tiles: 117 (~ 12% of series production)
- tiles which passed the tests: 117
- rejected tiles: 0
The works are in schedule
Thank you for your attention!