Proposal for a Coordinated Research Project:
Prediction of Axial and Radial Creep in Pressure Tubes
Patricia B.Bozzano - ARGENTINA Vienna, july 2013
Embalse Nuclear Power Plant
• POTENCIA TÉRMICA: 2.109 MWt • POTENCIA ELÉCTRICA BRUTA/NETA: 648 Mwe • MODERADOR Y REFRIGERANTE: Agua pesada (D2O) • COMBUSTIBLE: Uranio natural • GENERADOR DE VAPOR: Cuatro verticales, tubos en "U" Incolloy
800TURBINAUna etapa de alta presión, tres etapas de baja presión . Velocidad:1.500 rpm
• GENERADOR ELÉCTRICO: Cuatro polos. • Tensión: 22 KV, 50 Hz
Laboratory for Testing Materials
PT - TASKS ISO 9001 Certification
• Rolled Joint Strength-Fracture Toughness: Fracture
Lab. Responsible: F. Iorio. • KIH – DHC velocity: Hydrogen Damage and Fracture
Labs. Responsible: G. Domizzi. • Hydride orientation: Hydrogen Damage and
Metallographic Labs. Responsible: G. Domizzi. • Alpha grains and Beta phase thickness:
Metallography and Electron Microscopy Lab. Responsible: P. Bozzano.
• Texture – Dislocation density: X-Ray Diffraction Lab. Responsible: N. Mingolo.
Rolled Joint Strength-Fracture Toughness
FRACTURE AND FATIGUE LAB
12 Profesionals - 6 Technicians
Facilities:
Thermo-mechanical lab.
Mechanical testing labs.
Metallographic lab.
FRACTURE AND FATIGUE LAB.
BACKGROUND
1.-Round Robin Test on Fracture Toughness of PT. (1993, AECL CRNL) Participant Labs.(9)
2.- CANDU Pressure Tubes Surveillance program (CNE).
3.-Fracture Assessment of NDT Indications During GS Repositioning in CNE
FRACTURE AND FATIGUE LAB.
– 1.-Round Robin Test on Fracture Toughness of PT. (1993, AECL CRNL))
Participants Labs.(9)
• (Canada)- AECL-CRNL; AECL-WRNE; HYDRO QUEBEC; ONTARIO HYDRO.
• (Japan)- HITACHI; PNC; KOBE STEEL. • (UK)- AEA-TECH. • (Argentina) CNEA MATERIALS: (3).- Zr-2.5%Nb (CW); Zr-2.5%Nb (HT); Zry-2
FRACTURE AND FATIGUE LAB.
Robin Test on Fracture Toughness of PT. STANDARD:”Standard Test Method for Fracture Toughness
of CANDU PT”
Material: Zr-2.5%Nb HT
FRACTURE AND FATIGUE LAB. Robin Test on Fracture Toughness of PT.
Material: Zr-2.5%Nb CW
FRACTURE AND FATIGUE LAB.
Robin Test on Fracture Toughness of PT.
Material: Zry-2
FRACTURE AND FATIGUE LAB.
POST IRRADIATION STUDIES ON CNE PT at CNEA HOT CELLS
• HWR Surveillance program, set 2 testing
• HWR Surveillance program, IAEA Reference material testing.
• HWR Control rod failure analysis.
• CANDU Pressure Tubes Surveillance program
FRACTURE AND FATIGUE LAB.
2. CANDU Pressure Tubes Surveillance program
TASKS: •Measurement of diameter and thickness. •Tensile properties. •Fracture Toughness.
Hot cells used during the study
Pressure tube sections
Specimens extraction program
█ Position 12 hs
█ Position 3 hs
█ Position 6 hs
█ Position 9 hs
Section of tube after specimens extraction
FRACTURE AND FATIGUE LAB.
Fracture toughness results
0 1 2 3 4 5 6 7 8 9 10 11
0
50
100
150
200
250
300
350
400
A14
L12
other reactors
dJ/d
a (
MP
a)
Fluence ( n/m2 x 10
25)
T=2500C
FRACTURE AND FATIGUE LAB.
3.- .-Fracture Assessment of NDT Indications
During GS Repositioning in CNE
During periodic outages of CNE, Fuel Channel Inspections are performed for GS spacers repositioning and PT/CT gap measurements. Assessment of reportable indications of flaws detected by NDT was carried out from the beginning of such works in 1991.
Hydrogen Damage Labs
Facilites:
•Gaseous Charge (Sievert)
•Chatodic charge
•Tensile strength, weight dead machines (Two)
•Acoustic Emission device
KIH – DHC velocity
IAEA COORDINATED RESEARCH PROGRAMME ON INTERCOMPARISON OF TECHNIQUES FOR PRESSURE TUBE
INSPECTION AND DIAGNOSTICS CRP: I3.30.10 Determination of hydrogen in zirconium alloy components and
Blister characterization by in-situ NDE techniques
Participating labs. Canada, Korea, China. Romania, Argentina
Participation of Argentina:
• hydrogen charge of
•90 samples for hydrogen determination: IGF, HVEMS, DSC, Resistivity, DTA
•17 samples for non destructive techniques
•6 blisters in CANDU pressure tube sections for NDT evaluation
Hydrogen Charge
Background:
Hydrogen concentration: results of IAEA INTERCOMPARISON
0 10 20 30 40 50 60 70 80 90 1000
20
40
60
80
100
Me
asu
red
co
nce
ntr
atio
n (
pp
mw
)
gaseous charge concentration (ppmw)
Arg1-2nd (IGF)
Arg2-2nd (IGF)
Korea (IGF)
India (IGF)
Canada (HVEMS)
India (HVEMS)
KIH – DHC velocity DHC Background
• CCT samples fatigue pre-cracked used in CANDU Pressure Tubes Surveillance program
• IAEA COORDINATED RESEARCH PROJECT “Determination crack growth speed during DHC of Zirconium alloys of” CNEA - IAEA Research Agreement Nº 10698/R0. (DCPD)
• Effect of heat treatment on Vp (AE)
IAEA COORDINATED RESEARCH PROJECT
Vp measured by DCPD (CORROSION LAB)
Efect of heat treatment on Vp
1.9 1.92 1.94 1.96 1.98 2 2.02
10-7.9
10-7.7
10-7.5
10-7.3
1000/T(K)
Vp
[m
/s]
380 ºC
430 ºC
500 ºC
Vp measured by AE
Correlation between Vp and cumulative counts:
nondestructive tool for DHC velocity estimation during the
test
0 1 2 3 4 5 6 7
x 10-8
0
1
2
3
4
5
6
7
8x 10
4
Velocity [m/s]
Nc,
Cu
mu
lati
ve
Co
un
t R
ate
.
Hydride distribution, Alpha grains
and Beta phase thickness
Hydrogen Damage, Metallograhy and
Electron Microscopy Labs
•Optical Microscopy •Scanning Electron Microscopy (SEM) •Transmission Electron Microscopy (TEM)
FEI Quanta 200 (HV, LV, ESEM) SyS software for image analisys
Philips CM200 with EDS
Background
• Microstructural characterization of 285 off-cuts of pressure tubes of CNE
•Morpholgy, size and distribution of phases α and β
•Hydride distribution, size and morphology
•Vickers microhardness with 100 grs. Average 235 Hv100
•Morpholgy, size and distribution of carbide precipitates.
• CANDU P Tubes Surveillance program
• Hydride distribution of A-14 and L-12 PT of CNE.
Texture – Dislocation density X-Rays Diffraction Lab
Facilities:
• Philips X-PERT crystallographic texture, Residual stresses and diffraction profiles analysis
• Philips PW 310 difractometer.
Crystallographic texture determination in Zr-
alloys pressure tube materials:
Measurements of direct pole figures (PF) from x-ray
diffraction in different directions of tube: radial (DR),
transverse (DT), axial (DA).
Evaluation of Fd texture factor (Kearns´factor)
calculated from experimental basal (0002) pole figures
for the three principal directions of the tube:
X-Ray Diffraction Laboratory: Background
Pole figures (0002) obtained with Cu-K radiation for differents
sections of Zr-2.5%Nb tube
(a) transverse section , FWHM=0.444o
(b) radial section, FWHM=0.373o
(c) axial section , FWHM=0.399o.
FWHM: full width at half maximum
(a) (b)
(c)
DT//DN DR//DN
DA//DN
X-ray diffraction line profile analysis from
patterns diffraction data and Rietveld refinement
for peak profile:
Analysis of peak broadening (FWHM) caused by the crystalline sizes
and microstrain
X-ray diffraction pattern for the Zr-2.5% Nb tube pressure from transverse
section (DN//DT). FWHM: full width at half maximum
Evaluation of dislocation densities in plastically deformed material from
the peak broadening information.
•According to the CPR, we can participate in the microstructure characterization
of pressure tubes materials.
•Our Laboratory for Testing Materials has IRAM – ISO 9001:2008 and IQNet
certification and AECL qualification for design, development and technical
reports of the following tests:
•Tensile test and fracture strength (K1; J1; R curve) in metallic materials at low
and high temperature.
•Fatigue crack growth in metallic materials.
•Determinations of: Vickers micro hardness, Rockwell B, Rockwell C, Brinell
and Vickers Hardness.
•Hydriding: gaseous charge in metallic materials and cathodic charge in Zr and
Zr alloys
•Determination of crack velocity propagation and measurement of the critical
stress intensity factor (K1H) by delayed hydride cracking in hydride forming
alloys.
•Corrosion tests in autoclave for Hafnium, Zirconium and their alloys.
•Metallography samples preparation and Vickers micro hardness.
•Scanning electron microscopy: obtaining micrographs and measurements in all
type of materials and Qualitative X - Ray energy dispersive spectroscopy.
•X- Ray Diffraction in crystalline materials for texture determination,
dislocations density and phase distribution in crystalline alloys.