Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell &...
-
Upload
brock-holliman -
Category
Documents
-
view
218 -
download
1
Transcript of Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell &...
![Page 1: Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell & Gary S. Was University of Michigan Research Supported.](https://reader035.fdocuments.us/reader035/viewer/2022062712/56649c7b5503460f9492f9db/html5/thumbnails/1.jpg)
Investigation of Proton Irradiation-Induced Creep of
Ultrafine Grain Graphite
Anne A. Campbell & Gary S. Was
University of MichiganResearch Supported by
US DOE under NERI Contract # FC07-06ID14732
And INL under Contract # DE-AC07-05ID14517
![Page 2: Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell & Gary S. Was University of Michigan Research Supported.](https://reader035.fdocuments.us/reader035/viewer/2022062712/56649c7b5503460f9492f9db/html5/thumbnails/2.jpg)
Outline
• Objective• Background• Experimental Setup & Procedure• Research Approach• Results• Comparison with Neutron Data• Summary
2
![Page 3: Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell & Gary S. Was University of Michigan Research Supported.](https://reader035.fdocuments.us/reader035/viewer/2022062712/56649c7b5503460f9492f9db/html5/thumbnails/3.jpg)
Objective
• Investigate the irradiation-induced creep of ultra-fine grain graphite– Study the effect of stress, dose rate, and temperature on
creep rate
• Compare results with neutron irradiation-induced creep work
3
![Page 4: Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell & Gary S. Was University of Michigan Research Supported.](https://reader035.fdocuments.us/reader035/viewer/2022062712/56649c7b5503460f9492f9db/html5/thumbnails/4.jpg)
Background
• Using POCO grade ZXF-5Q– Particle size < 1 µm– Density 1.78g/cm3
– Tensile Strength 79 MPa– Anisotropy < 1.03 BAF– Young’s Modulus 14.5 GPa
• Using 3 MeV protons for radiation damage and heating– 3 MeV used to keep damage rate ratio
from front to back of sample below 1.5 (from SRIM calculations)
– 70 µm maximum sample thickness– Final sample size 3mm x 0.07 mm x 33
mm (cut via EDM)
4
POCO Grade ZXF-5Q Data sheet.
![Page 5: Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell & Gary S. Was University of Michigan Research Supported.](https://reader035.fdocuments.us/reader035/viewer/2022062712/56649c7b5503460f9492f9db/html5/thumbnails/5.jpg)
Experiment – Irradiation Chamber
5
Campbell, A.A. and G. S. Was, Journal of Nuclear Materials, 433 (2013) 86-94.
![Page 6: Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell & Gary S. Was University of Michigan Research Supported.](https://reader035.fdocuments.us/reader035/viewer/2022062712/56649c7b5503460f9492f9db/html5/thumbnails/6.jpg)
Experiment – Irradiation Stage
6
![Page 7: Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell & Gary S. Was University of Michigan Research Supported.](https://reader035.fdocuments.us/reader035/viewer/2022062712/56649c7b5503460f9492f9db/html5/thumbnails/7.jpg)
Laser Speckle Extensometer (LSE)
7
Camera
Laser
AnalysisProgram Sample
![Page 8: Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell & Gary S. Was University of Michigan Research Supported.](https://reader035.fdocuments.us/reader035/viewer/2022062712/56649c7b5503460f9492f9db/html5/thumbnails/8.jpg)
2D Thermal Imager
8
![Page 9: Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell & Gary S. Was University of Michigan Research Supported.](https://reader035.fdocuments.us/reader035/viewer/2022062712/56649c7b5503460f9492f9db/html5/thumbnails/9.jpg)
Irradiation Creep Experimental Procedure
• Assemble stage, test heater, mount samples, apply and remove tensile load on bench-top, align and test beam apertures
• Assemble chamber on beam-line, insert load, insert stage, align LSE, apply load to sample, seal top port, pump out chamber, start LSE DVRT and Stage data collection, condition vacuum, align 2D thermal imager start temperature collection
• Obtain desired proton current in Faraday cup, increase beam scanner to wider than necessary, apply beam to samples, balance beam one apertures, narrow scanner width until desired temperature is achieved, set alarms for temperature and dose rate monitoring and control
• Analyze LSE and DVRT data to determine linear fit and 95% CI of slope, continue at same conditions until 95% CI < 1% of the slope or desired final dose is achieved, change to other conditions or end experiment
• Insert Faraday cup, cool system to room temperature, remove stress from sample, vent vacuum chamber, remove stage, remove samples from stage, put individual samples in boxes labeled with all relevant irradiation information
9
![Page 10: Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell & Gary S. Was University of Michigan Research Supported.](https://reader035.fdocuments.us/reader035/viewer/2022062712/56649c7b5503460f9492f9db/html5/thumbnails/10.jpg)
Irradiation Creep Example Data
10
![Page 11: Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell & Gary S. Was University of Michigan Research Supported.](https://reader035.fdocuments.us/reader035/viewer/2022062712/56649c7b5503460f9492f9db/html5/thumbnails/11.jpg)
Dose Rate & Temperature Control
11
![Page 12: Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell & Gary S. Was University of Michigan Research Supported.](https://reader035.fdocuments.us/reader035/viewer/2022062712/56649c7b5503460f9492f9db/html5/thumbnails/12.jpg)
Irradiation Creep Experimental Conditions
• Applied tensile stress (1000ºC, 1.15x10-6dpa/s)– 5 MPa, 10 MPa, 20 MPa, 40 MPa
• Dose Rate (700ºC, 20MPa)– 2.95x10-7dpa/s to 5.51x10-7dpa/s
• Temperature (20MPa, variable dose rate)– 700ºC, 900ºC, 1000ºC, 1100ºC, 1200ºC
• Two samples used for each experiment, one with stress and one without stress– Residual stress from EDM machining resulted in curvature of the
unstressed sample
12
![Page 13: Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell & Gary S. Was University of Michigan Research Supported.](https://reader035.fdocuments.us/reader035/viewer/2022062712/56649c7b5503460f9492f9db/html5/thumbnails/13.jpg)
Applied Stress Dependence
13
![Page 14: Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell & Gary S. Was University of Michigan Research Supported.](https://reader035.fdocuments.us/reader035/viewer/2022062712/56649c7b5503460f9492f9db/html5/thumbnails/14.jpg)
Dose Rate Dependence
14
![Page 15: Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell & Gary S. Was University of Michigan Research Supported.](https://reader035.fdocuments.us/reader035/viewer/2022062712/56649c7b5503460f9492f9db/html5/thumbnails/15.jpg)
Temperature Dependence
15
![Page 16: Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell & Gary S. Was University of Michigan Research Supported.](https://reader035.fdocuments.us/reader035/viewer/2022062712/56649c7b5503460f9492f9db/html5/thumbnails/16.jpg)
Accumulated Dose Dependence
16
![Page 17: Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell & Gary S. Was University of Michigan Research Supported.](https://reader035.fdocuments.us/reader035/viewer/2022062712/56649c7b5503460f9492f9db/html5/thumbnails/17.jpg)
Stress Dependence Comparison
17
Gray, Carbon, 11, (1973) 183 Oku et al., JNM, 152, (1988) 225Oku et al., JNM, 172, (1990) 77
![Page 18: Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell & Gary S. Was University of Michigan Research Supported.](https://reader035.fdocuments.us/reader035/viewer/2022062712/56649c7b5503460f9492f9db/html5/thumbnails/18.jpg)
Dose Rate Comparison
18
Veringa and Blackstone, Carbon, 14, (1976) 279.Oku et al., JNM, 152, (1988) 225 Oku et al., JNM, 172, (1990) 77
![Page 19: Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell & Gary S. Was University of Michigan Research Supported.](https://reader035.fdocuments.us/reader035/viewer/2022062712/56649c7b5503460f9492f9db/html5/thumbnails/19.jpg)
Accumulated Dose Comparison
19
Neutron Data for H-451 from:Burchell, T.D., JNM, 381, (2008) 46.
![Page 20: Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell & Gary S. Was University of Michigan Research Supported.](https://reader035.fdocuments.us/reader035/viewer/2022062712/56649c7b5503460f9492f9db/html5/thumbnails/20.jpg)
Temperature Comparison
20
Veringa and Blackstone, Carbon, 14, (1976) 279. Burchell, T.D., JNM, 381, (2008) 46.Gray et al., Carbon, 5, (1967) 173 Kelly and Burchell, Carbon, 32, (1994) 119.Mitchell et al., Nuclear Energy, 41, (2002) 63 Oku et al., JNM, 152, (1988) 225Oku et al., JNM, 172, (1990) 77 Perks and Simmons, Carbon, 1, (1964) 441.Perks and Simmons, Carbon, 4, (1966) 85.
![Page 21: Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell & Gary S. Was University of Michigan Research Supported.](https://reader035.fdocuments.us/reader035/viewer/2022062712/56649c7b5503460f9492f9db/html5/thumbnails/21.jpg)
Possible Source of Discrepancy
• Protons provide both displacement damage and heating from electronic excitation– Damage comes from PKA interaction– Fundamentally similar PKA interaction within material
• Neutron irradiations have both neutron and γ-rays interacting with material
21
![Page 22: Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell & Gary S. Was University of Michigan Research Supported.](https://reader035.fdocuments.us/reader035/viewer/2022062712/56649c7b5503460f9492f9db/html5/thumbnails/22.jpg)
γ – Ray Effects
• Work in Russia– Examined effect of
Radiation Composition Factor (RCF=ϕn/ϕγ) on Turn-around dose (Fcrit)
• Use equation to determine effective temperature (i.e. temperature without γ-rays)
22
MR (0.13)
SM-2 (0.1)
BOR-60 (4)
2
5 2
0.18 19.85
2.440.0721* 7.49 10
ncrit cm
irr irr
F E MeV
T C x T CRCF
Nikolaenko et al., Atomic Energy, 87, (1999) 480.
![Page 23: Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell & Gary S. Was University of Michigan Research Supported.](https://reader035.fdocuments.us/reader035/viewer/2022062712/56649c7b5503460f9492f9db/html5/thumbnails/23.jpg)
Burchell, T.D., "Neutron Irradiation Damage in Graphite and Its Effects on Properties", Presented at International Carbon Conference CARBON 2002, Beijing, China, September 15-20, 2002.
Neutron Results – H-451
23
Temp (ºC)
Fluence (n/m2 E>0.1MeV)
Fluence (n/cm2 E>0.18MeV)
RCF ϕn/ϕγ
Equivalent Temp (ºC)
(ϕγ=0)
kE0 (dpa)-1
600 2.5x1026 20.5x1021 0.156 950 2.65900 1x1026 8.2x1021 0.154 1100 4.56
2
5 2 2.440.18 19.85 0.0721* 7.49 10n
crit irr irrcmF E MeV T C x T C
RCF
![Page 24: Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell & Gary S. Was University of Michigan Research Supported.](https://reader035.fdocuments.us/reader035/viewer/2022062712/56649c7b5503460f9492f9db/html5/thumbnails/24.jpg)
Proton Results
24
Temperature (ºC)
Dose Rate (dpa/s) Drad (cm2/s) kE0 (dpa)-1
from DVRT900 8.1x10-7 2.30x10-18 27.55 (6.04)1100 15.6x10-7 2.81x10-17 51.51950* 9.9x10-7 4.72x10-18 32.88
0
0
1100 51.511.29
4.56900
p
n
kE C
kE C
0
0
950 32.8812.41
2.65600
p
n
kE C
kE C
17
18
1100 2.81 1012.2
2.30 10900rad
rad
D C x
xD C
![Page 25: Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell & Gary S. Was University of Michigan Research Supported.](https://reader035.fdocuments.us/reader035/viewer/2022062712/56649c7b5503460f9492f9db/html5/thumbnails/25.jpg)
Discussion of Analysis
• Russian researchers proposed that γ-rays interact and produce fast electrons that stimulate diffusion processes
• Recent work in China investigated the effects of γ-rays, on graphite, at room temperature– Shows that γ-rays can increase graphitization of graphite at room
temperature
• Possible that γ-rays are annealing damage as it is being caused by neutrons in-reactor, effectively reducing the # of defects available to assist with driving creep
25
Li, B. et al., Carbon, 60, (2013) 186. Xu, Z. et al., Materials Letters, 63, (2009) 1814.
γ dose (MGy) D002 (nm) Lc (002) (nm) D002 (nm) % Graphitized
0 0.3372 [Li] 26.4 [Li] 0.3376 [Xu] 75 [Xu]
0.200 0.3361 [Li] 31.7 [Li]
2.00 0.3366 [Li] 31.0 [Li] 0.3371 [Xu] 81 [Xu]
![Page 26: Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell & Gary S. Was University of Michigan Research Supported.](https://reader035.fdocuments.us/reader035/viewer/2022062712/56649c7b5503460f9492f9db/html5/thumbnails/26.jpg)
Summary
• Proton Irradiation-Induced creep experiments preformed on POCO ZXF-5Q graphite– Investigated stress, dose rate, temperature, and accumulated
dose effects on creep behavior
• Linear dependence on stress, dose rate, and temperature trends agree with neutron creep measurements
• Compliance values for protons factor of 6-10 higher than neutron values– Experimental results suggest creep is driven by defect
population and γ-rays reduces the defect population, which reduces creep rate
26
![Page 27: Investigation of Proton Irradiation-Induced Creep of Ultrafine Grain Graphite Anne A. Campbell & Gary S. Was University of Michigan Research Supported.](https://reader035.fdocuments.us/reader035/viewer/2022062712/56649c7b5503460f9492f9db/html5/thumbnails/27.jpg)
Investigation of Proton Irradiation-Induced Creep of
Ultrafine Grain Graphite
Anne A. Campbell & Gary S. Was
University of MichiganResearch Supported by
US DOE under NERI Contract # FC07-06ID14732
And INL under Contract # DE-AC07-05ID14517