Upload
nguyenkhuong
View
224
Download
3
Embed Size (px)
Citation preview
Materials Characterization for Generation IV Reactors
Natalia Luzginova
4th Nordic Seminar on Generation IV Nuclear Reactors
Risø, Denmark
29-31 October 2012
Outline
Introduction
Materials Characterization projects
ARCHER
o Post Irradiation Examination (PIE) of HTR graphite
grades
o Characterization of alloy 800H
GETMAT
o PIE of structural materials after irradiation in Lead
Bismuth Eutectic (LBE)
o Assessment of alternative joining techniques for
advanced materials
MATTER
o Fracture toughness testing in LBE
o Negligible creep domain definition
NRG provides consultancy services and products based on nuclear technology
Over 350 employees
First-rate nuclear R&D infrastructure, including a High Flux Reactor and Hot Cell Laboratories
Focus on three key areas:
R&D and support for existing reactors; and innovative systems including
fusion and fission reactors
Radiation protection and waste management services
Radioisotopes for medicine and industry
Introduction
Outline
Introduction
Materials Characterization projects
ARCHER
o Post Irradiation Examination (PIE) of HTR graphite
grades
o Characterization of alloy 800H
GETMAT
o PIE of structural materials after irradiation in Lead
Bismuth Eutectic (LBE)
o Assessment of alternative joining techniques for
advanced materials
MATTER
o Fracture toughness testing in LBE
o Negligible creep domain definition
PIE of HTR graphite grades
Graphite is used as a neutron moderator and reflector material
(AGR, Magnox, RBMK, MTR, HTR)
For HTR design a database containing behavior of different
graphite grades under irradiation at temperatures relevant for
HTRs is being created
Main aim is to investigate changes of HTR graphite properties
due to neutron irradiation between 650 and 950 °C
M.C.R. Heijna, J.A. Vreeling
INGSM-13 (2012)
PIE of HTR graphite grades
INNOGRAPH experiments
Four irradiation experiments
~ 600 irradiated graphite
samples
Graphite grades from Toyo
Tanso, SGL Carbon and
GrafTech International
included
o Pet and pitch coke
grades included
o Extruded, iso-moulded
and vibro-moulded
grades included
M.C.R. Heijna, J.A. Vreeling
INGSM-13 (2012)
Low dose Medium dose High dose
PIE of HTR graphite grades
Experiment is designed to allow loading and assembling in
hot cell
Each experiment contains 24 thermocouples and 9
dosimeter sets
~ 180 samples per experiment
PIE of HTR graphite grades
Measured materials properties
Volume and length change
Young’s modulus
Thermal expansion and diffusivity
Microscopy
Strength properties
XRD and XRT
M.C.R. Heijna, J.A. Vreeling
INGSM-13 (2012)
PIE of HTR graphite grades
M.C.R. Heijna, J.A. Vreeling, INGSM-13 (2012)
0.0 2.5 5.0 7.5 10.0 12.5 15.0 17.5 20.0 22.5 25.0
-10
-5
0
5
10
15
20
25
0.0 2.5 5.0 7.5 10.0 12.5 15.0 17.5 20.0 22.5 25.0
-10
-5
0
5
10
15
20
25
0.0 2.5 5.0 7.5 10.0 12.5 15.0 17.5 20.0 22.5 25.0
-10
-5
0
5
10
15
20
25
0.0 2.5 5.0 7.5 10.0 12.5 15.0 17.5 20.0 22.5 25.0
-10
-5
0
5
10
15
20
25
650°C
750°C
850°C
950°C
V
/V0 (
%)
650°C
750°C
850°C
950°C
650°C
750°C
850°C
950°C
V
/V0 (
%)
dpa
650°C
750°C
850°C
950°C
dpa
Extrusion Extrusion
Iso-moulding Vibro-moulding
PIE of HTR graphite grades
Conclusions
4 irradiation experiments are successfully completed
providing HTR relevant data (well beyond of “turn around”)
It is shown that the rate of material property changes is
(strongly) temperature dependent
New irradiation experiment coming up to cover missing
information at low dose
Low dose Medium dose High doseM.C.R. Heijna, J.A. Vreeling, INGSM-13 (2012)
Outline
Introduction
Materials Characterization projects
ARCHER
o Post Irradiation Examination (PIE) of HTR graphite
grades
o Characterization of alloy 800H
GETMAT
o PIE of structural materials after irradiation in Lead
Bismuth Eutectic (LBE)
o Assessment of alternative joining techniques for
advanced materials
MATTER
o Fracture toughness testing in LBE
o Negligible creep domain definition
Alternative joining techniques
Ferritic-martensitic (FM) steels (9-12 wt.% Cr) and Oxide
Dispersion Strengthened (ODS) FM steels are promising
candidate materials for Gen4 fission and fusion reactors
Conventional welding of these steels without destroying
the characteristic microstructure is a challenge
In this research, feasibility of
pioneering non-fusion
welding techniques such as
Friction Stir Welding (FSW) is
performed to join these
advanced steels
P. Yvon et al, 2009
Friction Stir Welding
TWI’s high precision FSW machine
located in South Yorkshire, UK. P91 steel plates (300 x 90 x 6.5 mm)
Fixtures (a) (c)
P 91 plate
P 91 plate Friction Stir Weld
(b)
M. Kolluri, N.V. Luzginova, E. W. Schuring, W. Kyffin, J. Martin, 9th ISFSW (2012)
Friction Stir Welding (FSW)
Tool material selection
Preliminary trials are performed with two front running tool materials
Tool design suitable for each material was selected based on prior
successful experience on austenitic stainless steels
W-Re tool material:
W-25% Re tool
W-Re/cBN tool material:
60-70% c-BN in a W-25% Re matrix tool
M. Kolluri, N.V. Luzginova, E. W. Schuring, W. Kyffin, J. Martin, 9th ISFSW (2012)
Friction Stir Welding (FSW)
Measured materials properties
Tensile and notched tensile tests
Impact properties
Fracture toughness
Hardness
Microscopy
Strength properties
M. Kolluri, T. Bakker, H. Nolles, P. ten Pierick, N.V. Luzginova, E. W. Schuring, J. Martin, NuMat 2012
FSW: tensile properties
M. Kolluri, T. Bakker, H. Nolles, P. ten Pierick, N.V. Luzginova, E. W. Schuring, J. Martin, NuMat 2012
FSW: tensile properties
M. Kolluri, T. Bakker, H. Nolles, P. ten Pierick, N.V. Luzginova, E. W. Schuring, J. Martin, NuMat 2012
FSW: impact properties
M. Kolluri, T. Bakker, H. Nolles, P. ten Pierick, N.V. Luzginova, E. W. Schuring, J. Martin, NuMat 2012
FSW: hardness
M. Kolluri, T. Bakker, H. Nolles, P. ten Pierick, N.V. Luzginova, E. W. Schuring, J. Martin, NuMat 2012
FSW: conclusions
FS welded specimens has shown superior tensile strength properties
than the base material and a considerable reduction in the ductility.
Application of PWHT helps to partially recover the ductility
A substantial increase in DBTT was observed due to FSW. Application of
PWHT reduces hardness of the weldment and recovers the impact
properties
Several recrystallized regions of soft ferrite was observed in the cap and
root regions of TMAZ of the weld after PWHT.
Proper control of gain refinement in the TMAZ during FSW, in order to
avoid PWHT, is key for the application this method for joining of the
selected steels for nuclear applications
M. Kolluri, T. Bakker, H. Nolles, P. ten Pierick, N.V. Luzginova, E. W. Schuring, J. Martin, NuMat 2012
Outline
Introduction
Materials Characterization projects
ARCHER
o Post Irradiation Examination (PIE) of HTR graphite
grades
o Characterization of alloy 800H
GETMAT
o PIE of structural materials after irradiation in Lead
Bismuth Eutectic (LBE)
o Assessment of alternative joining techniques for
advanced materials
MATTER
o Fracture toughness testing in LBE
o Negligible creep domain definition
Fracture toughness testing in LBE
Liquid metal embrittlement (LME)
“Reduction of ductility and fracture
toughness of metals when simultaneously
subjected to stresses and wetting by liquid
metals” E. Glickman, 2000
LME can be influenced by a large
number of testing parameters
There is a large scatter during testing
in liquid metal
Main goals:
Development of the guidelines for
fracture toughness (FT) testing in LBE
Evaluations and verifications of FT in
LBE
LFR pilot plant (MYRRHA)
Fracture toughness testing in LBE
A new test set-up has been developed by NRG for fracture
toughness tests in LBE
3-tank system set-up
Set-up is designed to fit into the
hot cell
Instron 1343 hydraulic testing
frame with a 25 kN load cell
M. Jong, D.A. Boomstra, H.S. Nolles, G. van der Meij, N.V. Luzginova, MUNECO 2012
Fracture toughness testing in LBE
The crack propagation will be
calculated from the load line
displacement measured by
means of two displacement
transducers
Measurement method is
evaluated at 250 oC in air (with
DCPD, LVDT and multi
specimen method)
Current specimens size is ½T
C(T) specimens
Adaptable to tensile and 1T
C(T) specimens
M. Jong, D.A. Boomstra, H.S. Nolles, G. van der Meij, N.V. Luzginova, MUNECO 2012
Fracture toughness testing in LBE
Active oxygen control system (produced by KIT)
Preconditioning of LBE in the storage tank, final conditioning in the test
tank
2 oxygen sensors in test tank and 1 oxygen sensor in the storage tank
O2 sensors
M. Jong, D.A. Boomstra, H.S. Nolles, G. van der Meij, N.V. Luzginova, MUNECO 2012
Fracture toughness testing in LBE
Conclusions
FTT set-up including oxygen control system is installed
and commissioned
Fracture Toughness Test Set-up Oxygen control system
M. Jong, D.A. Boomstra, H.S. Nolles, G. van der Meij, N.V. Luzginova, MUNECO 2012