Abstract

Zr–2.5Nb Alloy is used in a cold-worked and stress-relieved (CWSR) condition as pressure tubes in Indian pressurized heavy water reactors (IPHWR). The life-limiting factor for pressure tubes is in-reactor dimensional changes caused by irradiation growth and creep resulting in diametral expansion and axial elongation. Recent work has indicated that heat-treated Zr–2.5Nb alloy may exhibit lower in-reactor dimensional changes vis-à-vis CWSR pressure tubes. The advanced heavy water reactor (AHWR) specification demands more stringent operating condition for the pressure tubes and it was decided to develop a new fabrication route for heat-treated Zr–2.5Nb alloy for possible application as pressure tubes in AHWR. In this work, the microstructural characterization and tensile properties evaluation was carried out using samples obtained from various stage of fabrication of water-quenched and aged Zr–2.5Nb alloy following a route similar to Fugen pressure tubes is discussed. The microstructure was characterized using optical and transmission electron microscopy. The chemical composition, morphology, and location of the precipitates formed during aging were studied using thin-foil electron microscopy and carbon extraction replica. Samples with its axes parallel to longitudinal (L) or transverse (T) direction of rolled plate were machined from quenched, cold-rolled, and aged material and were tested in tension at 25°C and 300°C. The microstructure and the tensile strength of the alloy processed in the present investigation were comparable to that of heat-treated pressure tubes used in Reaktor Bolshoy Moshchnosti Kanalniy (RBMK) and Fugen reactors.

Issue Section:
Research Papers
Keywords:
heat-treated Zr–2.5Nb alloy, advanced heavy water reactor, microstructure, tensile properties

References

1.
Singh
,
R. N.
,
Mukherjee
,
S.
,
Kishore
,
R.
, and
Kashyap
,
B. P.
, “
Flow Behaviour of a Modified Zr–2.5 wt. %Nb Pressure Tube Alloy
,”
J. Nucl. Mater.
, Vol.
345
,
2005
, pp.
146
–
161
. https://doi.org/10.1016/j.jnucmat.2005.05.008
Google Scholar
Crossref
Search ADS
 
2.
Srivastava
,
D.
,
Dey
,
G. K.
, and
Banerjee
,
S.
, “
Evolution of Microstructure during Fabrication of Zr–2.5 wt. %Nb Alloy Pressure Tubes
,”
Metall. Trans. A
, Vol.
26A
,
1995
, pp.
2707
–
2718
. https://doi.org/10.1007/BF02669427
3.
Coleman
,
C. E.
,
Cheadle
,
B. A.
,
Cann
,
C. D.
, and
Theaker
,
J. R.
, “
Development of Pressure Tubes With Service Life Greater than 30 Years
,”
Zirconium in the Nuclear Industry: 11th International Symposium, ASTM STP 1295
,
Garmisch-Partenkirchen
,
Germany
, September 11–14,
1995
,
E. R.
 
Bradley
 and
G. P.
 
Sabol
, Eds.,
1996
, pp.
884
–
898
.
Google Scholar
Crossref
Search ADS
 
4.
Theaker
,
J. R.
,
Choubey
,
R.
,
Moan
,
G. D.
,
Aldridge
,
S. A.
,
Davis
,
L.
,
Graham
,
R. A.
, and
Coleman
,
C. E.
, “
Fabrication of Zr–2.5Nb Pressure Tubes to Minimize the Harmful Effects of Trace Elements
,”
Zirconium in the Nuclear Industry: 10th International Symposium, ASTM STP 1245
,
Baltimore, MD
, June 21–24,
1993
,
E. R.
 
Bradley
 and
G. P.
 
Sabol
, Eds.,
1994
, pp.
221
–
242
.
Google Scholar
Crossref
Search ADS
 
5.
Fleck
,
R. G.
,
Price
,
E. G.
, and
Cheadle
,
B. A.
, “
Pressure Tube Development for CANDU Reactors
,”
Zirconium in the Nuclear Industry: ASTM STP 824
,
D. G.
 
Franklin
 and
R. B.
 
Adamson
, Eds.,
ASTM International
,
West Conshohocken, PA
,
1984
, p. 88.
Google Scholar
Crossref
Search ADS
 
6.
Ross-Ross
,
P. A.
 and
Fidleris
,
V.
, “
Design Basis for Creep of Zirconium Alloy Components in a Fast Neutron Flux
,”
Proceedings of the International Conference on Creep and Fatigue in Elevated Temperature Applications
,
Philadelphia, PA
, September 23—27
1973
, Paper C216, pp. 216.1–216.7.
7.
Coleman
,
C.
,
Griffiths
,
M.
,
Grigoriev
,
V.
,
Kiseliov
,
V.
,
Rodchenkov
,
B.
, and
Markelov
,
V.
, “
Mechanical Properties of Zr–2.5Nb Pressure Tubes Made from Electrolytic Powder
,”
J. ASTM Int.
, Vol.
4
(
10
),
2007
, Paper ID JAI101111. https://doi.org/10.1520/JAI101111
8.
Koike
,
M.
 and
Asada
,
T.
, “
Irradiation Creep and Growth of Pressure Tubes in HWR Fugen
,”
J. Nucl. Mater.
, Vol.
159
,
1988
, pp.
62
–
74
. https://doi.org/10.1016/0022-3115(88)90085-2
Google Scholar
Crossref
Search ADS
 
9.
Koike
,
M. H.
,
Onose
,
S.
,
Nagamatsu
,
K.
, and
Kawajiri
,
M.
, “
Hydrogen Pick-up and Degradation of Heat-Treated Zr–2.5Nb Pressure Tubes
,”
JSME Int. J.
, Vol.
B36
(
3
),
1993
, pp.
464
–
470
. https://doi.org/10.1299/jsmeb.36.464
10.
Holt
,
R. A.
, “
In-Reactor Deformation of Cold-Worked Zr–2.5Nb Pressure Tubes
,”
J. Nucl. Mater.
, Vol.
372
,
2008
, pp.
182
–
214
. https://doi.org/10.1016/j.jnucmat.2007.02.017
Google Scholar
Crossref
Search ADS
 
11.
Bickel
,
G. A.
 and
Griffiths
,
M.
, “
Manufacturing Variability, Microstructure, and Deformation of Zr–2.5Nb Pressure Tubes
,”
J. ASTM Int.
, Vol.
4
(
10
),
2007
, Paper ID JAI101126. https://doi.org/10.1520/JAI101126
12.
Nikulina
,
A. V.
,
Reshetnikov
,
N. G.
,
Shebaldov
,
P. V.
,
Ageenkova
,
L. E.
,
Fomin
,
V. S.
,
Shevnin
,
Y. P.
, and
Kochergin
,
S. A.
, “
Fabrication Technology of RBMK Zr-2.5–Nb Pressure Tubes
,”
Voprosy Atomnoy Nauki i Tekhniki, Ser. Mater. Sci. Novel Mater.
, Vol.
36
(
2
),
1990
, pp.
46
–
54
.
13.
Fidleris
,
V.
, “
The Creep Strength of Quenched and Aged Zr–2.5 wt. %Nb Alloy
,”
J. Nucl. Mater.
, Vol.
54
,
1974
, pp.
199
–
211
. https://doi.org/10.1016/0022-3115(74)90130-5
Google Scholar
Crossref
Search ADS
 
14.
Banerjee
,
S.
 and
Mukhopadhyay
,
P.
, “
Phase Transformations: Examples from Titanium and Zirconium Alloys
,”
Pergamon Materials Series
, 1st ed.,
R. W.
 
Cahn
, Ed.,
Pergamon
,
Oxford
,
2007
.
15.
Grytsyna
,
V.
,
Stukalov
,
A.
,
Chernyayeva
,
T.
,
Krasnorutskyy
,
V.
,
Malykhin
,
D.
,
Voyevodin
,
V.
, and
Bryk
,
V.
, “
Destruction of Crystallographic Texture in Zirconium Alloy Tubes
,”
J. ASTM Int.
, Vol.
2
(
8
),
2005
, Paper ID JAI12339. https://doi.org/10.1520/JAI12339
16.
Bell
,
L. G.
 and
Dick
,
T. S.
, “
The Effect of Prior Beta Grain-Size on the Ductility of Zirconium-2.5 Weight Percent Niobium Alloy
,”
Can. Metall. Q.
, Vol.
4
,
1965
, p. 259. https://doi.org/10.1179/000844365795164783
17.
Hunt
,
C. E. L.
 and
Niessen
,
P.
, “
The Continuous Cooling Transformation Behaviour of Zirconium–Niobium–Oxygen Alloys
,”
J. Nucl. Mater.
, Vol.
38
,
1971
, pp.
17
–
25
. https://doi.org/10.1016/0022-3115(71)90003-1
Google Scholar
Crossref
Search ADS
 
18.
Choubey
,
R.
 and
Jackman
,
J. A.
, “
Microsegregation of Oxygen in Zr–2.5Nb Alloy Materials
,”
Metall. Mater. Trans. A.
, Vol.
27A
,
1996
, pp.
431
–
440
. https://doi.org/10.1007/BF02648420
19.
Banerjee
,
S.
,
Vijayakar
,
S. J.
, and
Krishnan
,
R.
, “
Precipitation in Zirconium–Niobium Martensites
,”
J. Nucl. Mater.
, Vol.
62
,
1976
, pp.
229
–
239
. https://doi.org/10.1016/0022-3115(76)90019-2
Google Scholar
Crossref
Search ADS
 
20.
Urbanic
,
V. F.
 and
Griffiths
,
M.
, “
Microstructural Aspects of Corrosion and Hydrogen Ingress in Zr–2.5Nb
,”
Zirconium in the Nuclear Industry: 12th International Symposium, ASTM STP 1354
,
G. P.
 
Sabol
 and
G. D.
 
Moan
, Eds.,
ASTM International
,
West Conshohocken, PA
,
2000
, pp.
641
–
657
.
Google Scholar
Crossref
Search ADS
 
21.
Ibrahim
,
E. F.
, “
In-Reactor Creep of Zr–2.5Nb Tubes at 570 K
,”
Zirconium in Nuclear Applications, ASTM STP 551
, Vol.
1974
,
ASTM International
,
West Conshohocken, PA
, pp.
249
–
262
.
Crossref
Search ADS
 
22.
Shishov
,
V. N.
,
Peregud
,
M. M.
,
Nikulina
,
A. V.
,
Pimenov
,
Y. V.
,
Kobylyansky
,
G. P.
,
Novoselov
,
A. E.
,
Ostrovsky
,
Z. E.
, and
Obukhov
,
A. V.
, “
Influence of Structure—Phase State of Nb Containing Zr Alloys on Irradiation-Induced Growth
,”
J. ASTM Int.
, Vol.
2
(
8
),
2005
, Paper ID JAI12431. https://doi.org/10.1520/JAI12431
23.
Bergqvist
,
H.
,
Information and Communication Technology (ICT)
,
Functional Materials Division (FNM)
,
KTH Sweden
(unpublished).
24.
Kearns
,
J. J.
 and
Woods
,
C. R.
 “
Effect of Texture, Grain Size, and Cold Work on the Precipitation of Oriented Hydrides in Zircaloy Tubing and Plate
,”
J. Nucl. Mater.
, Vol.
20
,
1966
, pp.
241
–
261
. https://doi.org/10.1016/0022-3115(66)90036-5
Google Scholar
Crossref
Search ADS
 
25.
Kearns
,
J. J.
, “
On the Relationship among f Texture Factors for the Principal Planes for Zr, Hf and Ti alloys
,”
J. Nucl. Mater.
, Vol.
299
,
2001
, pp.
171
–
174
. https://doi.org/10.1016/S0022-3115(01)00686-9
Google Scholar
Crossref
Search ADS
 
26.
Northwood
,
D. O.
 and
Kosasih
,
U.
, “
Hydrides and Delayed Hydrogen Cracking in Zirconium and Its Alloys
,”
Int. Metals Rev.
, Vol.
28
(
2
),
1983
, p. 92. https://doi.org/10.1179/095066083790411759
This content is only available via PDF.
All rights reserved. This material may not be reproduced or copied, in whole or part, in any printed, mechanical, electronic, film, or other distribution and storage media, without the written consent of ASTM International.
You do not currently have access to this content.