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Training Symposium on Irradiation Effects in Structural Materials for Nuclear Reactors
17-21 September 2012 Seville
1.2. Irradiation Surveillance Programs and Integrity Concepts for Reactor Pressure Vessels
H. Hein
17-21 September 2012 2
Contents
Introduction
RPV Ageing Mechanisms
RPV Irradiation Surveillance Programs
RPV Integrity Concepts
Specific Issues in Irradiation Behaviour
Countermeasures
Outlook
References
17-21 September 2012 3
Introduction
Reactor Pressure Vessel (RPV) is very important for normal operation and safe inclusion of fission products
Fuel elements (core)
Physical barrier
Core cooling function
RPV is almost impossible to replace
Installation of the EPRTM RPV in Olkiluoto 3
2010
EPRTM (European
Pressurized Water Reactor)
17-21 September 2012 4
13
Introduction
RPV integrity is a design principle for safe inclusion of the activity inventory
to be maintained during operation
Requirement of both RPV monitoring and structural mechanical analyses
German PWR
1300 MW
13
2
1 RPV
Steam generator heat tubes
Main coolant lines
[1]
17-21 September 2012 5
RPV Ageing Mechanisms
Influencing factors
Irradiation by fast neutrons
Neutron generation in the core
Impact on RPV beltline
Gamma irradiation
Thermal loading by hot coolant
Some hydrogen by radiolysis and water chemistry regime
RPV of EPRTM [2] Tinlet=296 °C pop=155 bar
17-21 September 2012 6
RPV Ageing Mechanisms
Irradiation by fast neutrons
Formation of microstructural lattice defects
1MeV
Model concept according to Alfred Seeger [3]
17-21 September 2012 7
RPV Ageing Mechanisms
Impact of irradiation by fast neutrons (E > 1 MeV) on the microstructure in the RPV beltline region
Ferritic low alloy steel
Core
Axial
Neutron Fluence
150
0
150
10 0 10 - 1
cm
j rel
Matrix damage
Cu-Rich Precipitates (CRP)
with Ni, Mn, Si, …
P segregation on grain
boundary
17-21 September 2012 8
RPV Ageing Mechanisms
Impact of fast neutron fluence ( >1017 n/cm2) on the material properties in the RPV beltline region
17-21 September 2012 9
RPV Ageing Mechanisms
Thermal Ageing of RPV Materials
For western RPV steels with Cu ≤ 0.25% thermal ageing is not observed for T ≤ 325°C for long operating times
No thermal ageing in LWR RPV steels with Cu < 0.35% and T < 300 °C
Some significance in Magnox type reactors (UK) in C-Mn RPV steels with 360 °C exposure temperature
Other Influencing Factors
Hydrogen: no effect under operating conditions (embrittlement of ferritic RPV material by hydrogen no more detectable at 250°C )
Gamma irradiation: not significant at LWR operating temperatures due to strong annealing effects
• No indications of g-irradiation effect on change of material properties of ferritic RPV materials under operating conditions
• If any g effect would exist it is limited on the surface of inner RPV wall because the attenuation for g is higher than for neutrons
17-21 September 2012 10
RPV Irradiation Surveillance Programs
Management of RPV Irradiation Behavior
Irradiation Surveillance
Programs
Monitoring material changes
depending on neutron fluence
RPV Integrity Assessment
Fracture mechanics based
PTS analysis
p-T curves, in-service
pressure tests
Assessment
Core Loading Management
Low leakage
RPV Neutron Shielding
Dummy assemblies
Internals replacement
Thermal Annealing
Recovery heat treatment
Countermeasures
17-21 September 2012 11
RPV Irradiation Surveillance Programs
Objective
Measurement of strength and toughness properties of materials in the RPV core beltline region as a function of neutron irradiation by accelerated irradiation specimen capsules (position nearer to the core)
17-21 September 2012 12
RPV Irradiation Surveillance Programs
Base and weld materials are monitored in the RPV core beltline
Sampling
X
Y
Core weld
17-21 September 2012 13
RPV Irradiation Surveillance Programs
Implementation
Material lab Hot cells
Pre & post examination
Assessment of irradiation behaviour
Design and Manufacture
Report
17-21 September 2012 14
RPV Irradiation Surveillance Programs
Main steps
Manufacture of specimens, fluence dosimeters, temperature monitors, and capsules
Insertion, irradiation and take out of capsules
Transportation services
Radiochemical examinations and activity determination of neutron dosimeters
Neutron fluence calculations for specimens and RPV wall (Dosimetry)
Mechanical testing in the „Hot Cells“ laboratory (tensile, Charpy-V, fracture mechanical)
Evaluation of the results and RPV safety assessment according to regulatory requirements
17-21 September 2012 15
RPV Irradiation Surveillance Programs
Dosimetry - Dual concept of fast neutron fluence calculation
Data for theoretical calculation
of neutron fluence:
• core burn-up data
• geometry
• material data
• cross section library
(ENDF/B-VI)
Dosimetry data for
fluence detectors:
• 54Fe(n,p)54Mn
• 93Nb(n,n’)93mNb
(IRDF2002)
Detector activity
Irradiation history
Neutron transport
calculation
(MCNPX/DORT)
Theoretical
neutron fluence
Experimental
neutron fluence
Experimental fluence
calculation
(MONIKA)
Neutron spectra
Comparison of results
Benchmarking of theoretical calculations
Verification of theoretical approach
17-21 September 2012 16
RPV Irradiation Surveillance Programs
Dosimetry
Determination of fast neutron fluence (E > 1 MeV)
• at dosimeter positions
• in RPV wall
Dosimeters
• Internal dosimeters (inside RPV)
• External dosimeters (outside RPV)
RPV scraping samples
• Taken from cladding
17-21 September 2012 17
What else is important?
Take out position and orientation of specimens taken from the (original) material blocks
• Tension, Charpy and fracture toughness specimens shall be removed from 1⁄4-T or 3⁄4-T locations (base metal)
• Transverse specimens (T-L, longitudinal axis transverse to the main direction of forming)
Lead factor - the ratio of the peak neutron fluence (E > 1 MeV) of the specimens in a surveillance capsule to the peak neutron fluence (E > 1 MeV) at the reactor pressure vessel inside surface
• 1.5 ≤ LF ≤ 12 (Germany)
• 1.5 < LF < 5 (USA)
Number of the capsules and take out schedule
• Usually 2 to 6 capsules covering the reactor life
RPV Irradiation Surveillance Programs
17-21 September 2012 18
RPV Irradiation Surveillance Programs
How to use surveillance data for RPV integrity assessment?
0
20
40
60
80
100
120
-150 -100 -50 0 50
Temperature [°C]
Ch
arp
y E
ne
rgy [J]
DT41
0
50
100
150
200
-150 -100 -50 0 50
Temperature [°C]
Fra
ctu
re tou
gh
ness K
Ic
-1
/2 ]
plant spec. KIC - Curve
DT41 [M
Pa*m
plant spec. Cv Energy -T - Curve
unirradiated
adjusted versus RTNDT
RTNDTj = RTNDT + DT41
irradiated
adjusted versus
ASME KIC Curve [5]
RTNDT - Concept: RTNDTj = RTNDT + DT41
acc. to [4]
17-21 September 2012 19
RPV Integrity Concepts
The reference temperature (e.g. RTNDTj or RTT0[5]) governs the material resistance
Transients and LOCA govern the load path
Temperature (C)
Load Path
Material Resistance
Str
ess inte
nsity,
Fra
ctu
reto
ughne
ss
MP
am
a
K = a
acc. to [4]
17-21 September 2012 20
RPV Integrity Concepts
Areas of postulated flaws of the RPV [4]
CORE
Loadability
Change
of material properties
Defect size
EOL
BOL
irradiated BOL
unirradiated
Stress intensity factor Kl
Kl = KP + KT + KR KIC KIC
DT41
Temperature [ °C ]
KI, K
IC [
N m
m -3
/2 ]
Material resistance > operational loading
W
2c
a
M
a
2c
W
2c/a
= Shape factor
= Crack depth
= Crack length
= Wall thickness
=
KIC = f (T, RTNDT) > KI = f ( o, a, M)
Residual Life Assessment
by Fracture Mechanics
17-21 September 2012 21
RPV Integrity Concepts
Pressurized Thermal Shock (PTS) by Loss Of Coolant Accident (LOCA) [4]
RPV
A
A
view A
mixing water
hot water
pump
ECC
plume region
Fluid-Fluid-MixingRPV
A
A
view A
mixing water
hot water
pump
ECC
plume region
Fluid-Fluid-Mixing
pffff
postulatedleak
17-21 September 2012 22
RPV Integrity Concepts
Thermal hydraulics at PTS [4], [6]
Strip
cooling
Plume
cooling
17-21 September 2012 23
RPV Integrity Concepts
Thermal hydraulic and mechanical analyses at PTS by FEM [4], [8]
17-21 September 2012 24
RPV Integrity Concepts
Mechanical analysis of postulated flaws at PTS by FEM [4]
Heißseitiges Leck 200 cm²,Submodell für Riss im zylindrischen Bereich, Fehler 20 mm
NT1/20 01 /de/01 40
Anlage 15
PTS-Analyse: GKN 2, KKE, KKI 2, KKP 2, KKG/BKE
1
2
3
1
2
3
12
3
12
3
1
2
31
2
3
GrundwerkstoffPlattierung
2c
a
M uster der Rissgeom etrtrie
Heißseitiges Leck 200 cm²,Submodell für Stu tzenkantenriss, Fehler 20 mm
NT1/2001/de/0 283
Anlage 19
PTS-Analyse: G KN 2, KKE, KKI 2, KKP 2, KKG/BKE
12
3
12
3
12
3
12
3
12
3
12
3
Plattierung
WEZ
GW
Heißseitiges Leck 200 cm²,
Submodell für Riss im zylindrischen Bereich, Fehler 20 mm
NT1/20 01 /de/01 40
Anlage 15
PTS-Analyse: GKN 2, KKE, KKI 2, KKP 2, KKG/BKE
1
2
3
1
2
3
12
3
12
3
1
2
31
2
3
GrundwerkstoffPlattierung
2c
a
M uster der Rissgeom etrtrie
Heißseitiges Leck 200 cm²,Submodell für Stu tzenkantenriss, Fehler 20 mm
NT1/2001/de/0 283
Anlage 19
PTS-Analyse: G KN 2, KKE, KKI 2, KKP 2, KKG/BKE
12
3
12
3
12
3
12
3
12
3
12
3
Plattierung
WEZ
GW
Heißseitiges Leck 200 cm²,
Submodell für Riss im zylindrischen Bereich, Fehler 20 mm
NT1/20 01 /de/01 40
Anlage 15
PTS-Analyse: GKN 2, KKE, KKI 2, KKP 2, KKG/BKE
1
2
3
1
2
3
12
3
12
3
1
2
31
2
3
GrundwerkstoffPlattierung
2c
a
M uster der Rissgeom etrtrie
Heißseitiges Leck 200 cm²,Subm odell für Stu tzenkantenriss, Fehler 20 mm
NT1/2001/de/0 283
Anlage 19
PTS-Analyse: G KN 2, KKE, KKI 2, KKP 2, KKG/BKE
12
3
12
3
12
3
12
3
12
3
12
3
Plattierung
WEZ
GW
Heißseitiges Leck 200 cm²,
Submodell für Riss im zylindrischen Bereich, Fehler 20 mm
NT1/20 01 /de/01 40
Anlage 15
PTS-Analyse: GKN 2, KKE, KKI 2, KKP 2, KKG/BKE
1
2
3
1
2
3
12
3
12
3
1
2
31
2
3
GrundwerkstoffPlattierung
2c
a
M uster der Rissgeom etrtrie
Heißseitiges Leck 200 cm²,Submodell für Stu tzenkantenriss, Fehler 20 mm
NT1/2001/de/0 283
Anlage 19
PTS-Analyse: G KN 2, KKE, KKI 2, KKP 2, KKG/BKE
12
3
12
3
12
3
12
3
12
3
12
3
Plattierung
WEZ
GW
Example of crack
geometry
Base metalcladding
Betrachtete RDB-Bereiche
RPV Areas under consideration
Hot leg leak 200 cm², Submodel for crack in
cylindrical region, flaw depth 20 mm
Hot leg leak 200 cm², Submodel for crack in nozzle
region, flaw depth 20 mm
Example of crack
geometry
17-21 September 2012 25
RPV Integrity Concepts
Results of deterministic PTS analysis (example) [4]
Konvoi, cold leg nozzle, flaw depth 10 mm,
KI from J as a function of crack tip temperature
0
40
80
120
160
200
0 50 100 150 200 250 300
crack tip temperature [°C]
KI a
us
J [
MP
a√
m]
KIc(RTNDT (Tang.)= 1,5 °C)
KIc(RTNDT (Max.)= 13 °C)
KJ 015h hE_Stutzen_k 2SEP
KJ 025h hE_Stutzen_k 2SEP
KJ 100h hE_Stutzen_k 2SEP
KJ 040h kE_Stutzen_k 2SEP
KJ 100h kE_Stutzen_k 2SEP
KJ 50h 4SEPk_Stutzen_k
KJ 100h 4SEPk_Stutzen_k
KJ 200h 4SEPk_Stutzen _k
KJ 400h 4SEPk_Stutzen_k
leading transient
allowable material
toughness properties
17-21 September 2012 26
RPV Integrity Concepts
Probabilistic PTS analysis [8], [9], [10], [11], [12], [13]
Probability per year for failure and crack initiation of the RPV
Define PTS-Screening Criterion (allowed reference temperature for a maximum allowed failure probability, see [10])
Quantify the margins of the deterministic PTS analysis
17-21 September 2012 27
Specific Issues in Irradiation Behaviour
Long Term operation
Chemical composition
Neutron flux effects
Late blooming effects
Advantageous RPV design feature
Reconstitution technique
17-21 September 2012 28
Specific Issues in Irradiation Behaviour
Number of reactors in operation by age (as of 31 Dec. 2010)
Long Term Operation ( > 130 plants older than 30 years)
IAEA Reference Data Series No.2 2011 Edition Nuclear Power Reactors in the World [14]
17-21 September 2012 29
Specific Issues in Irradiation Behaviour
Background of Long Term Operation
Increasing age of the existing NPPs and envisaged lifetime extensions up to an EOL of 60 or even 80 years
Need for an improved understanding and prediction of RPV irradiation embrittlement effects under Long Term Operation (LTO)
Irradiation effects caused by high neutron fluences such as the possible formation of Late Blooming Phases and as yet other unknown defects must be considered adequately in safety assessments
In this context the availability of microstructural data is also essential for the understanding of the involved mechanisms
17-21 September 2012 30
Chemical composition
Impact of high contents of Cu and Ni in RPV steel welds on T41 shift
Low irradiation embrittlement for most of the irradiated materials except for weld metals P370 WM (0,22 % Cu) and P16 WM (1,7 % Ni)
High Cu or Ni
Low Cu and Ni
H. Hein, et al
“Final Results from the Crack Initiation and
Arrest of Irradiated Steel Materials Project on
Fracture Mechanical Assessments of Pre-
Irradiated RPV Steels Used in German PWR”
Journal of ASTM International (2010),
STP 1513 on Effects of Radiation on Nuclear
Materials and the Nuclear Fuel Cycle: 24th
Volume [15]
Specific Issues in Irradiation Behaviour
17-21 September 2012 31
Neutron flux effects
Flux effects may occur under certain conditions
0
50
100
150
200
0,0E+00 5,0E+19 1,0E+20 1,5E+20
Neutron Fluence [cm-2] (E > 1 MeV)
DT
41 [
K]
BM 174, surv. program, f =7.2E10 cm-2 sec-1
BM 174, inner irr. position, f =3.1E12 cm-2sec-1
BM 174, VAK, f =2.5E12 cm-2sec-1
22NiMoCr3-7 (0.1 % Cu)
H. Hein, J. May
“Review of irradiation surveillance and test reactor data of RPV
steels used in German LWR in relation to the flux effect issue” [16]
Workshop on Trend Curve Development for Surveillance Data with insight on Flux Effects at High Fluence: Damage
Mechanisms and Modeling, Mol (Belgium), November 19–21, 2008
G. R. Odette and T. Yamamoto
Neutron Irradiation Flux Effects on RPV Steels:
Analysis of the IVAR Database [17]
Specific Issues in Irradiation Behaviour
17-21 September 2012 32
0
50
100
150
200
0,0E+00 1,0E+19 2,0E+19 3,0E+19 4,0E+19
Neutron Fluence [cm -2] (E > 1 MeV)
DT
41 [
K]
WM 186 D, KWO, Cu = 0.22% f =6.1E10 cm-2 sec-1
WM 186 D, VAK, Cu = 0.22% f =2.1E12 cm-2 sec-1
WM 186 A, VAK, Cu = 0.14% f =2.6E12 cm-2 sec-1
WM 186 B, VAK, Cu = 0.30% f =2.6E12 cm-2 sec-1
WM 186 C, VAK, Cu = 0.42% f =2.6E12 cm-2 sec-1
Neutron flux effects
Example for high Cu weld data giving no effect on material properties
SANS results show flux effect on microstructure but not on
mechanical properties!
Bergner, A Ulbricht, H Hein and M Kammel:
Flux dependence of cluster formation in neutron irradiated
weld material
J. Phys.: Condens. Matter 20 (2008) 104262 (6pp) [19]
Flux ratio = 34
H. Hein, J. May
“Review of irradiation surveillance and test reactor data of RPV
steels used in German LWR in relation to the flux effect issue”
Workshop on Trend Curve Development for Surveillance Data with
insight on Flux Effects at High Fluence: Damage Mechanisms and
Modeling, Mol (Belgium), November 19–21, 2008 [18]
Specific Issues in Irradiation Behaviour
17-21 September 2012 33
Neutron flux effects
Flux effects could occur on a large scale of flux densities (φ < 1E+10 n/cm2/s to φ >> 1E+12 n/cm2/s) through different combining influences of specific features [20]
Some flux effects (usually higher DBTT shift at lower flux) observed in some Western LWR and in VVER, in particular for Cu rich RPV steels, however the issue is very complex and needs further clarification
• Surveillance lead factor: 1.5 …12 (German KTA 3203), 1.5 …5 (ASTM E 185)
Flux effects (if any) have to be taken into account for transferability of surveillance specimens and MTR results to RPV wall
Specific Issues in Irradiation Behaviour
17-21 September 2012 34
Late Blooming Effects
First findings by Odette et al
Possible significant increase of irradiation embrittlement at high fluences
• Low or no Cu content
• High Ni and Mn
• Low irradiation temperature
• High fluence (>>1E19 n/cm2, E>1MeV)
Specific Issues in Irradiation Behaviour
17-21 September 2012 35
Late Blooming Effects
Subject of LONGLIFE project [21]
0
50
100
150
200
250
300
350
0 5 10 15 20
neutron fluence (1019
n/cm², E>1MeV)
yie
ld s
tren
gth
in
crea
se (
MP
a)
JPB JPC JFL 0.05%Cu; 0.75%Ni; 0.08%P / 265°C
f 1.9 1012
n/cm².s
Tirrad=255 °C
f 4 1012
- 6 1013
n/cm².s
Tirrad=265 °CE. Altstadt, F. Bergner, H, Hein
“IRRADIATION DAMAGE AND
EMBRITTLEMENT IN RPV STEELS
UNDER THE ASPECT OF LONG TERM
OPERATION – OVERVIEW OF THE FP7
PROJECT LONGLIFE”
ICONE-18, Proceedings of the 18th
International Conference on Nuclear
Engineering ICONE18 May 17-21, 2010,
Xi'an, China [22]
Specific Issues in Irradiation Behaviour
17-21 September 2012 36
Advantageous RPV design feature: large water gap
Neutron fluences in n/cm2 ( E > 1 MeV) after 32 EFPY for German PWR [23]
2,8E19 1,3E19 1E19 3E18
Specific Issues in Irradiation Behaviour
17-21 September 2012 37
Reconstitution technique
Manufacture of new specimens from tested or untested (irradiated) specimens
Compact Crack Arrest (CCA) specimen
Single Edge Bending (SE(B)) specimen
Specific Issues in Irradiation Behaviour
17-21 September 2012 38
RPV
Core BarrelThermal Shield
RPV
Core BarrelThermal Shield
Countermeasures
Core Loading Management (reduction of neutron flux)
Low leakage core
• Changing from out-in fuel loading scheme (new fuel assembly at core edges) to in-out loading scheme (partly burnt-up fuel assembly at core periphery)
17-21 September 2012 39
Countermeasures
RPV Neutron Shielding (reduction of neutron flux)
Dummy assemblies
Internals replacement
Example for use of dummy or shielding assemblies at the core edge in the azimuthal region of the fluence maximum:
• fuel assemblies with high burn up and inserted absorber rods (AgInCd) • modified fuel assemblies with steel rods instead of fuel pellets • special steel elements
17-21 September 2012 40
Countermeasures
Thermal Annealing (recovery of material properties)
Recovery heat treatment
Thermal Annealing of VVER reactors [25]
41 J transition temperature shift in cyclic irradiation annealing experiments [24]
17-21 September 2012 41
Countermeasures
Increase the water temperature in the storage tanks of Emergency Core Cooling System (ECSS) [26]
Reduction of load in PTS case
17-21 September 2012 42
Outlook
Annual construction starts and connections to the grid (1954 - 2010)
Tendency of increasing number of new NPP builds
IAEA Reference Data Series No.2 2011 Edition Nuclear Power Reactors in the World [14]
17-21 September 2012 43
Outlook
RPV irradiation surveillance and safety assessment is an essential part of Plant Life Management and Plant Life Extension
Long term irradiation induced ageing phenomena
60+ operational years are on the agenda
Design life of 60 years for Generations III, III+ (EPR), IV
Life Time Extension activities for Generation II
• USA: extended license life renewals of many NPPs
• Europe: Switzerland, the Netherlands, France, Spain, Sweden, …
• Additional surveillance capsules have been inserted in a number of RPV, e.g. in The Netherlands, Sweden, Switzerland and Germany
17-21 September 2012 44
References
[1] Ilg, U., König, G., Erve, M., “Das Werkstoffkonzept in deutschen Leichwasserreaktoren – Beitrag zur Anlagensicheheit, Wirtschaftlichkeit und Schadensvorsorge”, International Journal for Nuclear Power, atw 53 (2008), No. 12
[2] http://www.areva-np.com/common/liblocal/docs/Brochure/BROCHURE_EPR_US_2.pdf
[3] A. Seeger, „Moderne Probleme der Metallphysik“, Erster Band, Springer-Verlag, Berlin ∙ Heidelberg ∙ New Yerk, 1965
[4] Keim, E., “RPV Integrity Assessment in Germany”, IAEA Regional Workshop on Structure, Systems and Components Integrity in Light Water Reactors, Belo Horizonte, Brazil, 23–26 June 2009
[5] ASME Boiler and Pressure Vessel Code, Section XI, Division 1, Appendix A, Article A-4000 Material Properties, 2007 Edition
[6] J. Barthelmes, E. Keim, H. Hein, A. de Jong Long Term Operation for Western Europe Nuclear Power Plants – RPV testing for Borssele PLEX, Nuclear Engineering International Magazine; August 2010
[7] ASME Boiler and Pressure Vessel Code, Section XI, Rules for In-service Inspection of Nuclear Power Plant Components, Code Case N-629, 1998 Edition
[8] “Pressurized Thermal Shock in Nuclear Power Plants: Good Practices for Assessment, Deterministic Evaluation for the Integrity of Reactor Pressure Vessel”, IAEA-TECDOC-1627, International Atomic Energy Agency, Vienna, 2010
[9] R. Tiete, Schlüter, N, “Probabilistic fracture mechanics: PTS Screening criteria for RTNDT, application of FAVOR code to a German KONVOI plant”, 20th International Conference on Structural Mechanics in Reactor Technology (SMiRT 20), Espoo, Finland, August 9-14, 2009
17-21 September 2012 45
References
[10] 10 CFR 50.61 “Fracture toughness requirements for protection against pressurized thermal shock events”, Code of Federal Regulations, U.S. Nuclear Regulatory Commission, December 2003[6]
[11] Simonen, F.A., S.R. Doctor, G.J. Schuster, and P.G. Heasler, “A Generalized Procedure for Generating Flaw Related Inputs for the FAVOR Code,” NUREG/CR-6817, U.S. Nuclear Regulatory Commission, October 2003
[12] EricksonKirk, M.T., Dickson, T.L., “Recommended Screening Limits for Pressurized Thermal Shock (PTS)”, NUREG CR-1874, U.S. Nuclear Regulatory Commission, March 2010
[13] Williams, P.T., and T.L. Dickson, “Fracture Analysis of Vessels Oak Ridge, FAVOR v04.1: Computer Code: Theory and Implementation of Algorithms, Methods, and Correlations,” NUREG/CR-6854, U.S. Nuclear Regulatory Commission, October, 2004
[14] IAEA Reference Data Series No.2 2011 Edition Nuclear Power Reactors in the World
[15] H. Hein, et al, “Final Results from the Crack Initiation and Arrest of Irradiated Steel Materials Project on Fracture Mechanical Assessments of Pre-Irradiated RPV Steels Used in German PWR”Journal of ASTM International (2010), STP 1513 on Effects of Radiation on Nuclear Materials and the Nuclear Fuel Cycle: 24th Volume
[16] H. Hein, J. May, “Review of irradiation surveillance and test reactor data of RPV steels used in German LWR in relation to the flux effect issue”, Workshop on Trend Curve Development for Surveillance Data With Insight on Flux Effects at High Fluence: Damage Mechanisms and Modeling, November 19-21, 2008, SCK CEN, Mol Belgium
[17] G. R. Odette and T. Yamamoto, “Neutron Irradiation Flux Effects on RPV Steels: Analysis of the IVAR Database”, Workshop on Trend Curve Development for Surveillance Data With Insight on Flux Effects at High Fluence: Damage Mechanisms and Modeling, November 19-21, 2008, SCK CEN, Mol Belgium
17-21 September 2012 46
References
[18] H. Hein, J. May, “Review of irradiation surveillance and test reactor data of RPV steels used in German LWR in relation to the flux effect issue”, Workshop on Trend Curve Development for Surveillance Data with insight on Flux Effects at High Fluence: Damage Mechanisms and Modeling, Mol (Belgium), November 19–21, 2008
[19] Bergner, A Ulbricht, H Hein and M Kammel, “Flux dependence of cluster formation in neutron irradiated weld material”, J. Phys.: Condens. Matter 20 (2008) 104262 (6pp)
[20] Odette, G.R., Lucas, G.E., "Embrittlement of Nuclear RPV steels“, Journal of Nuclear Materials 53 (2001) p. 18 – 22
[21] May, J., Hein, H., Altstadt, E., Bergner, F., Viehrig, H. W., Ulbricht, A., Chaouadi, R., Radiguet, B., Cammelli, S., Huang, H., Wilford, K., “FP7 project LONGLIFE: Treatment of long-term irradiation embrittlement effects in RPV safety assessment”, Third International Conference on Nuclear Power Plant Life Management, Salt Lake City, USA,14–18 May, 2012
[22] E. Altstadt, F. Bergner, H, Hein, “Irradiation damage and embrittlement in RPV steels under the aspect of long term operation - Overview of the FP7 project LONGLIFE”, ICONE-18, Proceedings of the 18th International Conference on Nuclear Engineering ICONE18, May 17-21, 2010, Xi'an, China
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References
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[26] 1st Nuclear Knowledge Preservation & Consolidation (NKP&C) Workshop WWER - WS1 Summary, European Commission, Joint Research Centre, Institute for Energy, EUR 23718 EN 2009