Transcript Radiation Effects WG 8th ITPA TG meeting on Diagnostics (14

10th ITPA TG Meeting on Diagnostics
10-14 April 06, Moscow
Radiation Effects WG
Eric Hodgson (presented by Benoit Brichard)
Input from JA: T.Nishitani, T.Shikama. RF: A. Krasilnikov, K.Vukolov. US: L.Snead
• Last meeting of Radiation Experts at 15th IEA Workshop held
during ICFRM-12 (Dec 05) in Santa Barbara. 18 people
attended the 4 1/2 h meeting.
• Updates on activities from EU, JA, RF, and US.
• 6-7 April EFDA Ceramics Irradiation meeting
• Now have ITER, but still waiting new structure for common
tasks.
EU update 1
EU laboratories involved in TW4/6-IRRCER programmes
AEUL Riga
CEA Cadarache
CIEMAT Madrid
IPP.CR Prague
FZK Karlsruhe
MEdC Bucharest
ÖAW Vienna
SCK/CEN Mol
Ferroelectric bolometers
NBI insulation
H/D/T effects, windows, bolometers, T/RIEMF , RIC/RIED
Hall probes
H/D/T effects, ECRH windows
Windows, fibres, optoelectronic components
Ferroelectric bolometers
Bolometers, fibres, T/RIEMF, RIED
EU update 2
• MI cables
(CIEMAT, SCK/CEN)
Combined effect of inhomogenieties,
transmutation/dpa and temperature gradient
RIEMF - serious problem - difficult to separate Rad. and T effects
TIEMF (centre conductor) detailed study (CIEMAT, SCK/CEN)
EMF (V)  T. No annealing of the effect observed up to 550 C
Not due to geometry
Need more data and experimental test
To fully understand further the combined RIEMF/TIEMF effect
Damage to MI cable Cu core
No TIEMF effect observed
in “normal” copper wire
“Normal” copper wire
Severe damage in Cu core
extracted from MI cable
Cause of TIEMF ?
Impurity analysis underway
copper core in MI cable !
Va
10
kΩ
Va
b
Vb
Core to Core induced voltage
10
kΩ
In-core irradiation in BR2
Cu
Transmutation ?
Change of seebeeck
coefficient
core-to-core voltage (µV) .
50
40
data
model
30
20
10
0
-10
29-11-05
06-12-05
13-12-05
20-12-05
13-12-05
20-12-05
Date
AISI304L
Is it radiation damage
related (Dpa) ?
core-to-core voltage (µV) .
20
15
10
5
0
-5
-10
-15
-20
29-11-05
data
model
06-12-05
Date
EU update 3
• Bolometers
(AEUL, CIEMAT, IPP, ÖAW, SCK/CEN)
JET resistance type:
Pt on Alumina and AlN
n irradiated - SCK/CEN --->
0.01 dpa, 400 C
PIE: Pt and substrates OK
Problem: electrical contacts
Ferroelectric type:
PbZrO3 being
prepared
Pt on Al2O3 and AlN
• Double Pt meanders
• Absorber, reverse side
• First check T and
ionization effects
550
Resistance, Ohm
510
600
Pt/AlN
500
400
470
T°C
300
430
Pt/Al2O3
390
Problem with electrical contact that
not withdstand high temperature
100
350
9/03/05
200
0
10/03/05
11/03/05
r1
r2
T1
T2
12/03/05
Temperature, C
Move to neutron
irradiation (BR2)
Good linearity of sensor
No change in resistance at 350°C up to 10-3 dpa
RIED in Al2O3
• Irradiation facility fully operational
– Active vaccuum, 10-2 mbar
– Active Heating up to 400°C
• 4.3 10-3 dpa => small differences (a few pA) are observed.
I - centre sample 12
log. I (A)
350
250
150
50
°C
-10.00
I-Centre before irr.
I-Centre after irr.
-11.00
-12.00
-13.00
1.00E-03
2.00E-03
3.00E-03
= > start of microstructural analysis
4.00E-03
Temp. 1/T (°K)
Pt on Si3N4
Also Pt on Si3N4 (IPP)
• IPP bolometer - “SiN” for
mica
• First check T and ionization
effects --->
No adverse effects
EU update 4
• Hall probes (IPP.CR, Ukraine)
InSb Hall devices (MSL, Lviv, Ukraine) showed acceptable
performance up to 10-3 dpa (70% of original sensitivity)
But upper temperature for operation is low (< 100C)
7 new sensors based on solid solutions of InSb and InAs and similar
materials with potential high T survival ( > 200°C )
1st in-reactor tests completed -->
But none survived beyond 10-3 dpa at 160-190 C.
Problems: electrical connections, solder joints, thin wire insulation ....
EU update 5
• Optical properties (CIEMAT, MEdC, SCK/CEN)
Enhanced surface degradation (optical and electrical)
from low energy H and He implantation. General problem ?
Mirrors: Coatings for extended UV reflectivity
No suitable UV fibres, and UV absorption extends to visible
H loading has limitations
Windows: High energy proton irradiations => for low dose  ≈ n
Window materials
450 ºC
250 ºC
102
50 ºC
100
10-2
10-4
10-6
1014
1015
1016
1017
Dose (ions/cm2)
1018
Optical Absorption (cm-1)
104
Optical absorption
Electrical current (µA)
2
1.5
50 ºC
1
250ºC
0.5
450 ºC
0
500
1000
1500
2000
2500
Wavelength (nm)
Si
16
Low energy He ion bombardment of KS-4V
Produces enhanced absorption and surface
electrical conductivity
XPS analysis shows extreme O loss
Results => Si and SiO rich surface zone
General problem for insulator surfaces ?
14
12
10
A.U
Electrical current (µA)
Surface degradation
8
O
Unimplanted
6
450ºC
4
250ºC
50 ºC
2
0
0.5
1
1.5
Energy (keV)
2
3000
Coated mirrors
Work on mirror coatings for general protection and LOCA
SiO2 (SiO) and alumina MgF (HfO2) for extended UV
No change when irradiated in N2 atmosphere but …
UV enhanced (Newport)
100
80
80
60
%R
%R
Visible enhanced (Coherent)
100
Coherent as rec
Coherent irrad 40MGy 170ºC N
60
Newport as rec
Newport irrad 40MGy 170ºC N
2
40
40
20
2
20
0
500
1000
1500
Wavelength (nm)
2000
2500
0
500
1000
1500
Wavelength (nm)
2000
2500
No protection against LOCA
• Radiation + humidity
• Degradation attacks the Al
coating even when protected
• Enhanced diffusion and
reactions (Al(OH)3)
• Swelling SiO -> SiO2
Usually, SiO2 better resistance against corrosion
EU update 6
• T diffusion / effects (CIEMAT, FZK)
Windows the primary barrier to confine tritium
Modelling on effects of H isotopes (T) in diamond indicates strong
trapping.
In-situ radiation enhanced diffusion in different materials is now being
measured.
Work starting on effects of H isotopes on physical properties
Radiation enhanced diffusion
electrons
Disc for analysis
• Disc samples electron
irradiated on vacuum side
• H/D on other side
• High sensitivity leak
detector for diffusion
• Pressure sensors for
absorption
H/D chamber
EU update 7
• EFDA Ceramics Irradiation Meeting 6-7 April 06
2 day meeting with presentations of all on-going EU TW5/6 tasks
Information / presentations shortly available
New data base task / specifications discussed
JA update
JAEA, NIFS, Tohoku IMF (Data from T.Shikama and T Nishitani )
RIC - stable insulators for blanket applications. Data for gamma, and
fission and fusion neutrons
Fast ion conductor behaviour during reactor irradiation
450 nm radioluminescence in silicas - band suppression with OH
content (full agreement with earlier data)
Radiation and temperature measurements using luminescence
Radiation induced conductivity (S/m)
10
-7
10
-8
10
-9
10
-10
10
-11
10
-12
10
-13
10
-14
10
▲ Y2O3
◆ CaZrO3
● Er2O3
Teruya Tanaka (NIFS) on
RIC of MHD insulators
for blanket application
Fission
reactor
Gamma ray
DT neutron
-4
10
-3
10
-2
10
-1
10
0
10
1
10
2
10
3
Dose rate (Gy/s)
-4
-4
10
Y2O3 (5.1 Gy/s, Bias: +250V)
-5
-6
10
Conductivity (S/m)
Conductivity (S/m)
10
-7
10
Under irradiation
-8
10
-9
10
-10
10
RIC
-11
10
Without
irradiation
-12
10
-13
10
-14
10
0
100
200
300
400
o
Temperature( C)
500
600
10
-5
10
-6
10
-7
10
-8
10
-9
10
-10
10
-11
10
-12
10
-13
10
-14
10
0
CaZrO3 (8.8 Gy/s, Bias: +250V)
Under irradiation
RIC
100
Without
irradiation
200
300
400
o
Temperature ( C)
500
600
Bun Tsuchiya JMTR irradiation: H-inplanted in ceramic material
Conclusion: RIC enhancement in H-inplanted material
Normalized luminescence intensity (arbitrary units)
Shinji Nagata on radioluminescence of silica
1000
+
17
2
1.5 MeV H 5 x 10 H/m
At very low fluences
800
600
0 ppm OH (T-2630)
200 ppm OH (T-2630)
800 ppm OH (T-2630)
3.1 eV: Intrinsic
B2βbands in low-OH silica
400
200
1000
0
+
19
2
1.5 MeV H 1 x 10 H/m
800
600
Under successive ion irradiation
Luminescence
decrease with
OH content
0 ppm OH
200 ppm OH
800 ppm OH
2.7 eV:
B2αbands in low-OH silica
1.9 eV:
NBOHC in high-OH silica
400
200
0
1.5
2.0
2.5
3.0
3.5
Photon energy (eV)
4.0
RF update
FORC, Kurchatov, TRINITI (Data from Anatoli Krasilnikov)
• Fibres – RL and RIA
Irradiations at IR-8 (Kurchatov)
At 3x1013 n/cm2/s, 400 Gy/s to 1018 n/cm2, 16 MGy
Fibres from FORC, Heraeus, Mitsubishi, and Fijukura
H loaded fibres give best results (lowest RL)
RL  reactor power (=> nuclear radiation monitor)
NO. FIBERS
1
2
KU-1
SSU
3
STU
4
SILICA ,
TYPE
The manufacturer
COATING
FORC
ALUMINIUM
HERAEUS QUARZGLAS GMBH & POLYMER
CO
HERAEUS QUARZGLAS GMBH & POLYMER
CO
MITSUBISH
POLYMER
MAIN IMPURITIES
OH~800 PPM, CL~140 PPM
OH~800 PPM
OH~20 PPM
OH~800 PPM, CL~140 PPM
FABRICATED,
PROBABLY ,
BY
THE
VADTECHNOLOGY
5
SILICA ,
FUJIKURA
POLYMER
FABRICATED,
PROBABLY ,
BY
THE
OH<20 PPM,
CLPROBABLY,
HIGH
CONCENTRATION
VADTECHNOLOGY
6
KU-1
FORC
ALUMINIUM
7
KS-4V-H2
FORC
ALUMINIUM
8
Silica,
fabrica ted by
the VAD technology
The silica core rod wa s fab ricated in theALUMINIUM
Tokyo Technology Institute.
The perform and the fiber
were fabricated in FORC
OH~800 PPM, CL~140 PPM,
H2-LOADED
OH 0.2 PPM, CL 20 PPM,
H2-LOADED
OH~3 PPM, CL~20 PPM,
H2-LOADED
H2
Loaded
Radiation induced luminescence spectra. Figures denote fibre numbers according to
Table 1. Fast neutron fluence - 4.71017 n/см2, gamma-dose –7.2 МGy(Si),
fast neutron fluxe -2.81013 n/см2 s, gamma-dose rate –400 Gy/s.
IR-8 reactor irradiation
Luminescence spectrum
2.0E-10
4
Luminescence spectra
corrected for re-absorption
2
1.0E-10
1
10000
1.E-10
1.E-11
100
1.E-12
1.E-13
6,7,8
1
0.0E+00
380
580
480
680
1.E-14
0
100
Irradiation time, h
200
nm
H2-loaded fibres
A.V. Bodarenko & al., instru. and exp. tech., 2006, Vol. 49, No2, pp 190-198
RL capacity, W/(nm*m)
3
Time evolution
Reactor power, kW
RL capacity, W/(nm*m)
3.0E-10
US update
ORNL (Data from L. Snead, D. Swain, D. Rasmussen, K. Leonard)
“Long ago” US was active during ITER CDA, on RIC in MI cables, RIED, windows
Now beginning activity once again:
ICRH insulators, thermal conductivity degradation, multilayer mirrors
Ion Cyclotron Insulators Radiation Effects
• Five ceramics (alumina in polycrystal and single crystal form)
– Al2O3 (Wesgo Al995, Deranox 999*); Al2O3 (Kyocera single crystal),
– BeO (Thermalox),
– AlN (Tokuyama SH-15),
– Si3N4 (Kyocera SN-235P),
– single crystal MgAl2O4 (Princeton Scientific Corp.)
• HFIR fission reactor irradiation at 80-100oC: 0.001, 0.01, 0.1 dpa (1018-1020
n/cm2, E>0.1 MeV)
• Pre- and post-irradiation testing of dielectric properties (dielectric constant, loss
tangent at ~100 MHz) and thermal conductivity
*Only one Deranox 999 specimen irradiated, at 0.1 dpa (material supplied by Eric
Hodgson)
Thermal Conductivity of Ceramics for Diagnostic Application
Theory is being developed to better understand defects
• Thermal conductivity in ceramic materials can be described as a summation of
various scattering centers for phonons as :
K (T)
1
 1
1
1
1 
 




K u (T) K gb (T) K d 0 K rd 
boundaries
Umklapp
intrinsic
(phonon
defects
Scattering)
radiation
defects
Thermal defect resistance
1
1
1


K rd K irr K unirr
• The appropriateness of addition of thermal resistances is suggested by the
addition of inverse relaxation times to obtain the combined relaxation time.
• Above 1/3 of the Debye temperature defect scattering is temperature independent.

60°C Neutron Irradiated Alumina
More complex defects formed during higher
dose irradiation are more thermally stable.
Defect Resistance 1/K
rd
(m-W/K)
0.016
Sapphire
0.014
Coors AD-998
Wesgo AL-998
0.012
Sapphire
Coors AD-998
0.010
Wesgo AL-998
0.008
0.01 dpa
0.006
0.004
0.002
0.001 dpa
0.000
0
200
400
600
800 1000
Annealing Temperature (C)
1200
Performance of Diaelectric Mirrors Under Irradiation
• Work just starting.
• Purpose : Development of multilayer dielectric and performance of these
materials under neutron and gamma irradiation.
• Approach: Fabrication of mirror structures without use of silica containing
layers.
- substrate materials, sapphire and silicon carbide
- layer materials:
Alumina
Magnesium aluminate spinel
Hafnium Oxide
Magnesium Oxide
• Intermediate dose irradiation to be carried out in June 06. (0.01 to ~ 1 dpa)