Materials for the ITER vacuum vessel and
in-vessel components – current status
V. Barabash, K. Ioki, M. Merola, G. Sannazzaro, N. Taylor
on behalf of the ITER Organization and the ITER Parties
First Joint ITER-IAEA Technical Meeting on
“Analysis of ITER Materials and Technologies”
23 – 25 November 2010
Principality of Monaco
Page 1
Outline
• Introduction
• Materials for the ITER vacuum vessel
− Structural
− In-Wall Shielding
• Materials for Blanket and Divertor
− Armour materials
− Structural and functional
• ITER Material Properties Handbook
• Summary
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 2
Main components and materials
Vacuum vessel:
-316L(N)-IG;
-304L, 304
-304B4, 304B7, 430
-Alloy 718, 660, XM-19
Blanket/First Wall:
-Beryllium;
-CuCrZr
-316L(N)-IG
-Ti alloy, Alloy 718,
Divertor:
-CFC and W;
-CuCrZr
-316L(N)-IG, XM-19
-NiAl bronze, 660
Cryostat:
- 304L and 304
Thermal Shield:
-304L;
-Alloy 718, Ti alloy,660
-G10, G11
Magnet System:
-Nb3Sn, NbTi, Cu
-316LN, JJ1, 316L
-Alloy 718,
-Epoxy, glass fiber
Diagnostic:
-Al203, single crystal
-Fused Silica, quartz
-Diamond, pure silica,
-Optical fibers
-Mirrors:Cu,W,MoSS,Al
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 3
Introduction
Design of the ITER Vacuum Vessel and divertor is completed and manufacture
of these components have been started in various DAs.
See poster presentations for details:
K. Ioki: Fabrication of ITER Vacuum Vessel
M. Merola: ITER Internal Components
T. Hirai: Status of ITER Divertor Procurement
Design of the ITER first wall and blanket is under finalization and ongoing in
accordance with schedule.
See poster presentations for details:
M. Merola: ITER Internal Components
R. Raffray: Status of ITER Blanket Design, R&D and Qualification
Materials for these components have been selected during design and R&D
phases and this selection has been justified and supported by extensive R&D
program carried out by ITER Parties.
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 4
Introduction
In general, the selection of materials has been based on comprehensive
assessment of the various functional, design, safety, operational and technological
requirements:
•
Armour materials – plasma compatibility, erosion lifetime, activation, etc.
•
Vacuum compatibility requirements
•
Magnetic properties requirements
•
Corrosion performance for materials in contact with coolant
•
Requirement to have appropriate mechanical properties for all operational
conditions and during all operational time
•
Technological properties (welding, brazing, etc.)
•
Radioprotection requirements (as low as reasonably achievable)
•
Cost consideration
The justification of the materials selection and main materials properties are
described in the ITER documents [Plant Description document, Material Properties
Handbook, etc.]
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 5
Materials for Vacuum Vessel
ITER Vacuum Vessel:
-
First barrier - Safety Important Component
Nuclear Pressure Equipment, Category IV, Nuclear level N2 in accordance with
French Order on Nuclear Pressure Equipments, Dec 2005.
Code – RCC-MR, Edition 2007
Materials requirements (NPE, Dec 2005):
Radioprotection requirements – limit of activated
corrosion products and waste class (Type A, [FMA])
for main materials:
-
Cobalt content
< 0.05 wt.%
Tantalum content < 0.01 wt.%
Niobium content < 0.01 wt.%
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 6
Materials for Vacuum Vessel
List of materials:
-
All pressure retaining materials are in conformity with NPE Order.
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 7
Materials for Vacuum Vessel
Main structural pressure retaining material - 316L(N)-IG
The steel 316L(N)-IG is selected based on more than 30 years’ experience of the
development of austenitic steels for fast-breeder reactor applications in France
and EU. As common for conventional 316L type grades, the steel has good
weldability and fabricability, and is available in a wide range of products.
In RCC-MR, Edition 2007, analogue of 316L(N)-IG steel is grade X2CrNiMo17-12-2
with controlled nitrogen content.
Corrosion behavior:
General corrosion – low
No stress corrosion cracking at specified water chemistry
Crevice corrosion – good resistance
No galvanic corrosion with other materials
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 8
Materials for Vacuum Vessel
Main structural pressure retaining material:
•
316L(N)-IG = X2CrNiMo17-12-2 controlled nitrogen content (RCC-MR
Code) + additional requirements for ITER application
Additional requirements to RCC-MR:
•
•
•
•
Radioprotection (Co, Nb, Ta)
Magnetic permeability < 1.03
Inclusion content (vacuum
requirements)
Additional limit for P, S
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 9
Materials for Vacuum Vessel
Borated steels for In-Wall Shielding:
- Function – improve shielding efficiency
- Non structural
ASTM A887:
•
•
•
Steel 304B4 with 1.00 - 1.25%B, grade B
Steel 304B7 with 1.75 – 2.25%B, grade B
Co and Nb limits as radioprotection
Selected:
•
•
Steel 304B4 produced by conventional
technique (elongation min - 16%)
Steel 304B7 – by powder metallurgy
(higher toughness,
elongation > 10%)
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
Courtesy
23 – 25 November 2010, Principality of Monaco
Page 10
Materials for Vacuum Vessel
Ferritic steel for In-Wall Shielding:
- Function – decrease magnetic ripples
- Non structural
ASTM A240/A240M:
•
•
Fe- 16.0 – 18.0% Cr
Co and Nb limits as radioprotection
Saturation magnetization is important
parameter for optimization of ripple:
•
Bs = 1.50 – 1.60 T is target at +/- 3%
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 11
Materials for Vacuum Vessel
Many standard materials are used for VV and ports:
•
1.4404 (316L), 1.4301 (304), 1.4307 (304L), XM-19, Alloy 718,
Alloy 625, Steel 660 (1.4980).
•
For all of them specific requirements for application were
determined and included in Procurement Specifications.
DAs involved in procurement of Vacuum Vessel and Ports
started (or very soon will start) procurement for
manufacture of these components.
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 12
In-Vessel Components
ITER In-Vessel Components Blanket, Divertor:
-
Non - Safety Important Component (no confinement of radioactivity)
Design Code – SDC-IV, manufacturing – EN standards + technical specifications
Assumed outside of scope of pressure equipment directive
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 13
First Wall - Blanket
List of materials:
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 14
Divertor
List of materials:
Note:
•
•
First divertor has CFC and W armour, following – only W
PFC of first divertor will be not irradiated – no requirements for radioprotection
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 15
Neutron Irradiation Conditions
Max.Neutron fluence - 0.5 MW*a/m2
10
Be
1.0E+15
Copper Alloy
Be surface
10 cm from Be surface
30 cm from Be surface
Austenitic Steel
1
1.0E+13
0.1
1.0E+11
0.01
0
10
20
30
Distance from First Wall, cm
40
50
1.0E+09
1.0E-05
1.0E-03
1.0E-01
1.0E+01
1.0E+03
Energy (MeV)
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 16
Armour materials
~ 680m2 Be first wall
low Z compatibility with wide operating range
and low T retention
~ 50 m2 CFC Divertor Target
No melting under transients (ELMs and Disruptions)
Low Z compatibility with wide range of plasma
regimes (Te,div ~ 1 – 100 eV)
Large T retention (co-deposition)
~ 100m2 Tungsten Divertor Dome, upper part of VT
Low Erosion, long Lifetime and low T retention
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 17
Armour materials - Beryllium
Reference grades:
•
•
•
S-65C VHP Brush-Wellman - the best thermal shock performance
RF and CN Parties propose their grades: TGP-56FW and CN-G01
All grades have < 1% BeO.
CN-G01, Transverse
350
CN-G01, Longitudinal
The acceptance of these grades will be done after additional
thermal fatigue and shock tests which shall demonstrate that their
performance is not significantly worse to behaviour of S-65C.
Yield strength, MPa
300
TGP56 FW, transverse, average
S-65C VHP, longitudinal
250
S-65C VHP, transverse
200
150
100
50
0
0
100
200
300
400
500
600
700
800
Temperature, C
CN-G01, Transverse
60
CN-G01, Longitudinal
TGP56 FW, transverse, average
50
S-65C VHP, longitudinal
Neutron effect:
– The behavior of all Be grades with Be0 < 1% is very similar.
Total elongation, %
S-65C VHP, transverse
40
30
20
10
0
0
100
200
300
400
500
600
700
800
Temperature, C
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 18
Armour materials - Beryllium
Importance of U impurity was recently assessed:
•
•
- Pu239 appears now in the top 13 of nuclides for their inhalation
- As a result it is proposed to include limit for U content in specification:
30 wppm maximum
Neutron effect:
– The behavior of all Be grades with Be0 < 1% is very similar.
- However, the performance of irradiated Be in the irradiated
components seems good, based on the results of in-pile tests and
test of FW mock-ups after irradiation
Average, unirradiated
Yield strength, unirr.
500
Yield Strength, irr
50
50
,R.Chaouadi, ~ 1 -2.5 dpa
40
300
30
200
20
100
Ttest = Tirr
0
0
100
200
300
400
Temperature, °C
500
600
700
Total Elongation, %
400
50
M.Roedig, 0.35 dpa
45
40
40
35
30
30
25
20
20
Ttest=Tirrad
10
10
0
0
S-65C/UTS
Yield Tensile Strength, MPa
Yield Strength, irr, L.Snead, 0.34 dpa~ 0.6 dpa
R. Chaouadi, 1-2.5 dpa
L.Snead, 0.34 dpa
15
10
5
0
0
200
400
600
800
Temperature, °C
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 19
Armour materials - Tungsten
Reference - pure sintered and rolled W
ASTM B 760 (Tungsten Plate, Sheet, and Foil )
+ additional requirements
Taniguchi, JAERI, 2000
Procurement specification requirements:
•
Chemical composition – min 99.94 % (ASTM)
•
Density – minimum 19.0 g/cm3
•
Stress relived condition (not recrystallised)
•
Grain size – Microstructure picture ( No. > 3)
•
Hardness (HV30 > 410)
•
NDE+QA
Performance of W significantly depends not only on
properties, but orientation of grains and production
history (plate, rod, swaged, etc.), heat treatment
condition (recrystallised), etc.
Recommendations (FDR 2001):
-Grain orientation perpendicular to joining surface
-Recrystallised W is not recommended
W
CuCrZr tube
Cu interlayer
Delamination
cracks
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 20
Armour materials - CFC
JA and EU DA are responsible for manufacture of
divertor Vertical Targets and CFCs are:
•
•
CX-2002U (Toyo Tanso, Japan)
2 grades under assessment in the EU
Procurement Specification includes main requirements:
Chemical composition (C> 99.99%);
Density: average and deviation
Thermal conductivity: max and average
Tensile properties
Q&A
600
NIC-01
Thermal conductivity, W/mK
•
•
•
•
•
500
Dunlop, C 1
CX 2002U
SEP NB 31
SEP NS 31
400
300
200
100
0
0
500
1000
1500
Temperature, °C
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 21
CuCrZr alloy
Reasons for modification of the chemical composition:
- smaller scatter of properties – higher minimum tensile properties
- less coarser Cr particles - toughness,
- better radiation resistance is expected,
- impurities – vacuum requirements
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 22
CuCrZr alloy
Three types of thermo-mechanical treatment were identified as most promising for
the various applications in ITER:
- solution annealing, cold working and ageing (SAcwA);
- solution annealing and ageing (SAA);
- solution annealing and ageing at non-optimal condition
(over-aged) due to specific manufacturing processes (SAoverA)
Su, min, SAA treatment
500
600
400
SAcwA treatment
Sy, min, SAA treatment
SAA treatment
500
Su, min, SAoverA treatment
400
Sy, min, SAoverA treatment
300
Su, MPH database
Su, min
200
300
200
Su, MPH data base
Su, min,
Sy, MPH data base
Sy, min
Su, average
Poly.
(Su, MPH data base)
Sy, average
Poly.
(Sy, MPH data base)
Sy, MPH database
Sy, min
100
100
Poly.
(Su, MPH database)
Su, average
Sy, average
Poly.
(Sy, MPH database)
0
0
100
200
300
Test Temperature, °C
400
500
Su, Sy, MPa
400
Su, Sy, MPa
Su, Sy, MPa
300
100
0
0
0
100
200
200
300
Test Temperature, °C
400
500
0
100
200
300
400
500
Test Temperature, °C
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 23
CuCrZr alloy
Significant amount of data about CuCrZr alloy
have been generated during worldwide R&D
=> See ITER MPH.
•
CuCrZr is most promising materials, however
some limits were identified
Nevertheless, still more data needed
Tensile strength at dose > 0.5 dpa
500
Minimum tensile strength Su, MPa
•
400
Creep
and
300
loss
200
Su, min SAcwA, unirradiated
of
Su, min SAA, unirradiated
100
Su, min, SAcwA, irradiated
strength
Su, min SAA, irradiated
0
0
100
200
300
400
Test Temperature, °C
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 24
Nickel Aluminum Bronze
NiAl bronze (CuAl10Ni5Fe4):
ASTM B150, ASTM B171M, C63200
EN 12163/12165
High strength, low friction and spark
resistance are the key properties.
Neutron effect:
Limited data are promising
20
1000
Ref. 1, Fabritsiev (Cu127), Ttest = Tirr = 150°C
Ref. 1, Fabritsiev (Cu127), Ttest = Tirr = 300°C
Elongation, %
Tensile strength, MPa
800
600
400
Un-irradiated
15
Total elongation, Ref. 1, Fabritsiev (Cu127), Ttest = Tirr = 150°C
Uniform elongation, Ref. 1, Fabritsiev (Cu127), Ttest = Tirr = 150°C
Total elongation, Ref. 1, Fabritsiev (Cu127), Ttest = Tirr = 300°C
Uniform elongation, Ref. 1, Fabritsiev (Cu127), Ttest = Tirr = 300°C
Un-irradiated
10
Trend at 150 C
Trend
5
200
Trend at 300C
0
0.0001
0
0.001
0.01
Damage dose, dpa
0.1
0
0.0001
0
0.001
0.01
0.1
Damage dose, dpa
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 25
Alloy 718
ASTM B637 (bars) UNS N07718
EN 10302:2002, No. 2.4668
y = e-0.694*x
Key issues:
•
-
Stress relaxation for bolting application:
Loss of strength at low damage dose:
effect is ~ 15%.
J.W. Rensman, MPH 2005; T.S. Byun, ORNL
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 26
Rewelding
Some in-vessel components will be changed during ITER
operation. Rewelding of irradiated materials will be
required.
To minimize the probability of crack formation during
re-welding, it is recommended to:
Minimize He content in the irradiated areas:
- < 0.5 -1 appm for multi-pass welding,
- < 1 - 3 appm for single pass (thin pipe) low energy welding.
The exact limitation of He content for sound re-weldability
depends on the welding method . This technology should
be carefully developed on the real components:
- Minimize the heat input during welding (TIG, NG, EB,
laser, magnetic-pulse welding).
- Minimize tensile stresses (compressive preferable).
- Use material with as low as possible boron content (e.g. 10 wt.
wppm)
Limit for Laser and TIG
for blanket pipe attachment
K. Asano, J. van der Laan, MAR, 2001
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 27
ITER MPH
The ITER Materials Handbook (MPH) was created in 1993 during the Engineering
Design Activities Phase ITER. This handbook was a cooperative activity between
the ITER Parties (at that time Japan, the European Union, the Russian Federation
and the US).
The goal of the MPH document was to provide ITER and the Parties with a single
reference source of material data. The data included in the MPH was assessed by
competent experts and formally approved by MPH Responsible Officer.
For the ITER Baseline the following structure of the ITER MPH is proposed:
1. ITER MPH Introduction (file: ITER_D_2NRCSB).
2. MPH-Part 1:
- Materials for vacuum vessel, in-vessel components, cryostat, thermal
shield components, tritium plant, cooling water system and cryoplant.
3. MPH-Part 2:
- Materials for superconducting magnets
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 28
ITER MPH
Further consolidation of the data and updating of the MPH
is going taking into project needs and latest R&D data
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 29
Summary
•
Materials for the ITER vacuum vessel and in-vessel components have
been selected based on comprehensive assessment of the functional,
operational, technological and radioprotection requirements.
Operational performance based on is justified by extensive analysis
and R&D.
•
The Procurement Arrangements for the ITER Vacuum Vessel and
divertor have been signed and Materials Procurement Specifications
have been prepared and agreed with potential Supplier.
•
For some components materials’ procurement have been started.
•
Further material data consolidation is still needed, especially for
components, for which design which is still under finalization.
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 30
Acknowledgement
Authors want to acknowledge many material scientists in the ITER
Domestic Agencies for their fruitful contribution to the materials’ selection
and enormous efforts on organizing R&D activity and establishing the
materials database which is needed for the justification of materials’
performance in ITER.
V. Barabash, First Joint ITER-IAEA Technical Meeting on “Analysis of ITER Materials and Technologies”,
23 – 25 November 2010, Principality of Monaco
Page 31