Abstract

Alloy 690 in the thermally treated (TT) condition is an advanced steam generator tubing material. The effect of thermal ageing treatments on the intergranular corrosion (IGC) behavior of the alloy was probed. Isothermal ageing was carried out at 600, 700, and 800°C with varying ageing time. Morphology of the carbides was studied as a function of thermal treatment temperature and duration. The carbides morphology was observed to affect the IGC resistance. Grain boundaries devoid of carbides (solutionized condition) or with coarse carbide particles (formed at 800°C) enhanced IGC resistance, whereas dendritic fine carbides formed at lower ageing temperature yield inferior IGC resistance.

Issue Section:
Research Papers
Keywords:
alloy 690, thermal treatment, grain boundary, carbide, intergranular corrosion

References

1.
Sui
,
G.
,
Titchmarsh
,
J. M.
,
Heys
,
G. B.
, and
Congleton
,
J.
, “
Stress Corrosion Cracking of Alloy 600 and Alloy 690 in Hydrogen/Steam at 380°C
,”
Corros. Sci.
, Vol.
39
, No.
3
,
1997
, pp.
565
–
587
. https://doi.org/10.1016/S0010-938X(97)86103-3
Google Scholar
Crossref
Search ADS
 
2.
De
,
P. K.
 and
Ghosal
,
S. K.
, “
A Comparative Study of Stress Corrosion Cracking of Steam Generator Tube Materials in Water at 315 C
,”
Corrosion
, Vol.
37
, No.
6
,
1981
, pp.
341
–
349
. https://doi.org/10.5006/1.3577283
Google Scholar
Crossref
Search ADS
 
3.
Lim
,
Y. S.
,
Kim
,
H. P.
,
Han
,
J. H.
,
Kim
,
J. S.
, and
Kwon
,
H. S.
, “
Influence of Laser Surface Melting on the Susceptibility to Intergranular Corrosion of Sensitized Alloy 600
,”
Corros. Sci.
, Vol.
43
, No.
7
,
2001
, pp.
1321
–
1335
. https://doi.org/10.1016/S0010-938X(00)00149-9
Google Scholar
Crossref
Search ADS
 
4.
Zagal
,
J. M.
,
López
,
H. F.
,
Flores
,
O.
,
Albarran
,
J. L.
, and
Martínez
,
L.
, “
Microstructural Effects on the Hydrogen Permeation of an Inconel Alloy 690
,”
Corros. Sci.
, Vol.
50
, No.
12
,
2008
, pp.
3371
–
3377
. https://doi.org/10.1016/j.corsci.2008.08.042
Google Scholar
Crossref
Search ADS
 
5.
Bruemmer
,
S. M.
 and
Henager
,
C. H.
, “
High Voltage Electron Microscopy Observations of Microdeformation in Alloy 600 Tubing
,”
Scr. Metall.
, Vol.
20
, No.
6
,
1986
, pp.
909
–
914
. https://doi.org/10.1016/0036-9748(86)90465-5
Google Scholar
Crossref
Search ADS
 
6.
Jiao
,
S. Y.
,
Zhang
,
M. C.
,
Zheng
,
L.
, and
Dong
,
J. X.
, “
Investigation of Carbide Precipitation Process and Chromium Depletion During Thermal Treatment of Alloy 690
,”
Metall. Mater. Trans. A
, Vol.
41
, No.
1
,
2010
, pp.
26
–
42
. https://doi.org/10.1007/s11661-009-0082-0
Google Scholar
Crossref
Search ADS
 
7.
Casales
,
M.
,
Salinas-Bravo
,
V. M.
,
Martinez-Villafane
,
A.
, and
Gonzalez-Rodriguez
,
J. G.
, “
Effect of Heat Treatment on the Stress Corrosion Cracking of Alloy 690
,”
Mater. Sci. Eng.
, Vol.
332
, Nos.
1–2
,
2002
, pp.
223
–
230
. https://doi.org/10.1016/S0921-5093(01)01747-6
8.
Norring
,
K.
,
Stiller
,
K.
, and
Nillson
,
J. O.
, “
Grain Boundary Microstructure, Chemistry and IGSCC in Alloy 600 and Alloy 690
,”
Fifth International Symposium on Environmental Degradation of Materials for Nuclear Power Systems–Water Reactors
,
Monterey, CA
, August
1991
,
American Nuclear Society
,
La Grange Park, IL
,
1991
, pp.
482
–
487
.
9.
Meng
,
F.
,
Wang
,
J.
,
Han
,
E.-H.
, and
Ke
,
W.
, “
The Role of TiN Inclusions in Stress Corrosion Crack Initiation for Alloy 690TT in High-Temperature and High-Pressure Water
,”
Corros. Sci.
, Vol.
52
, No.
3
,
2010
, pp.
927
–
932
. https://doi.org/10.1016/j.corsci.2009.11.015
Google Scholar
Crossref
Search ADS
 
10.
ASTM G108-94(2015),
Standard Test Method for Electrochemical Reactivation (EPR) for Detecting Sensitization of AISI Type 304 and 304L Stainless Steels
,
ASTM International
,
West Conshohocken, PA
,
2015
, www.astm.org
11.
Lin
,
P.
,
Palumbo
,
G.
,
Erb
,
U.
, and
Aust
,
K. T.
, “
Influence of Grain Boundary Character Distribution on Sensitization and Intergranular Corrosion of Alloy 600
,”
Scr. Metall. Mater.
, Vol.
33
, No.
9
,
1995
, pp.
1387
–
1392
. https://doi.org/10.1016/0956-716X(95)00420-Z
Google Scholar
Crossref
Search ADS
 
12.
Kim
,
S. H.
,
1998
, “
Thesis on Grain Boundary Character Distribution and Intergranular Corrosion in High Purity Aluminum
,” Ph.D. thesis,
University of Toronto
, Toronto, Canada.
13.
Weizhong
,
J. I. N.
,
Yang
,
S.
,
Kokawa
,
H.
,
Wang
,
Z.
, and
Yutaka
,
S. Sato.
, “
Improvement of Intergranular Stress Corrosion Crack Susceptibility of Austenite Stainless Steel Through Grain Boundary Engineering
,”
J. Mater. Sci. Technol.
, Vol.
23
,
2007
, pp.
785
–
789
.
14.
Li
,
H.
,
Xia
,
S.
,
Zhou
,
B.
,
Chen
,
W.
, and
Hu
,
C.
, “
The Dependence of Carbide Morphology on Grain Boundary Character in the Highly Twinned Alloy 690
,”
J. Nucl. Mater.
, Vol.
399
, No.
1
,
2010
, pp.
108
–
113
. https://doi.org/10.1016/j.jnucmat.2010.01.008
Google Scholar
Crossref
Search ADS
 
15.
Lim
,
Y. S.
,
Kim
,
J. S.
,
Kim
,
H. P.
, and
Cho
,
H. D.
, “
The Effect of Grain Boundary Misorientation on the Intergranular M23C6 Carbide Precipitation in Thermally Treated Alloy 690
,”
J. Nucl. Mat.
, Vol.
335
, No.
1
,
2004
, pp.
108
–
114
. https://doi.org/10.1016/j.jnucmat.2004.07.038
Google Scholar
Crossref
Search ADS
 
16.
Lewis
,
M. H.
 and
Hattersley
,
B.
, “
Precipitation of M23C6 in Austenitic Steels
,”
Acta. Metall.
, Vol.
13
, No.
11
,
1965
, pp.
1159
–
1168
. https://doi.org/10.1016/0001-6160(65)90053-2
Google Scholar
Crossref
Search ADS
 
17.
Li
,
H.
,
Xia
,
S.
,
Zhou
,
B.
, and
Liu
,
W.
, “
C-Cr Segregation at Grain Boundary Before the Carbide Nucleation in Alloy 690
,”
Mater. Charact.
, Vol.
66
,
2012
, pp.
68
–
74
. https://doi.org/10.1016/j.matchar.2012.02.008
Google Scholar
Crossref
Search ADS
 
18.
Jang
,
K. S.
,
Park
,
D. S.
,
Yu
,
Y. J.
,
Kim
,
J.
,
Min
,
N.
,
Hyun
,
S.
, and
Lee
,
K. J.
, “
Interpretation of Carbide Precipitation and Chromium Concentration Distribution of Alloy 690
,”
Appl. Mech. Mater.
Vol.
372
,
2013
, pp.
84
–
87
. https://doi.org/10.4028/www.scientific.net/AMM.372.84
Google Scholar
Crossref
Search ADS
 
19.
Sherry
,
A.
,
Beck
,
J. S.
, and
Cruddace
,
A. E.
,
Modern Power Station Practice, Vol. 5, Chemistry and Metallurgy
,
Reynolds
 
P. M.
, Ed.,
British Electricity International
,
London, UK
,
1982
.
20.
Thorvaldsson
,
T.
 and
Salwen
,
A.
, “
Measurement of Diffusion Coefficients for Cr at Low Temperatures in a Type 304 Stainless Steel
,”
Scr. Metall.
, Vol.
18
, No.
7
,
1984
, pp.
739
–
742
. https://doi.org/10.1016/0036-9748(84)90331-4
Google Scholar
Crossref
Search ADS
 
21.
Murr
,
L. E.
,
Wong
,
G. I.
, and
Horylev
,
R. J.
, “
Measurement of Interfacial Free Energies and Associated Temperature Coefficients in 304 Stainless Steel
,”
Acta. Metall.
, Vol.
21
, No.
5
,
1973
, pp.
595
–
604
. https://doi.org/10.1016/0001-6160(73)90068-0
Google Scholar
Crossref
Search ADS
 
22.
Stickler
,
R.
 and
Vinckier
,
A.
, “
Morphology of Grain-Boundary Carbides and Its Influence on Intergranular Corrosion of 304 Stainless Steel
,”
Trans. ASM
, Vol.
54
,
1961
, pp.
362
–
380
.
23.
Fricano
,
J. W.
,
2009
, “
Thesis on Chemical and Structural Analysis of Grain Boundaries in Inconel 690 for Corrosion Resistance
,” Ph.D. thesis,
Massachusetts Institute of Technology
, Cambridge, MA.
24.
Foll
,
H.
,
2016
, “
Defects In Crystals
,” http://www.tf.uni-kiel.de/matwis/amat/def_en/index.html (Last accessed 23 Feb 2016)
25.
Herbeuval
,
I.
 and
Biscondi
,
M.
, “
Diffusion of Zinc in Grains of Symmetric Flexion of Aluminium
,”
Can. Metall. Quart.
, Vol.
13
, No.
1
,
1974
, pp.
171
–
175
. https://doi.org/10.1179/cmq.1974.13.1.171
Google Scholar
Crossref
Search ADS
 
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.