High Cr ferritic heat resisting steels have been widely used for boiler components in ultrasupercritical thermal power plants operated at about 600°C. In the welded joint of these steels, type-IV crack initates in the fine-grained heat affected zone during long-term use at high temperatures and their creep strength decreases. In this paper, creep properties and creep crack growth (CCG) properties of P92 welds are presented. The CCG tests are carried out using cross-welded compact tension C(T) specimens at several temperatures. The crack front was located within the fine-grained HAZ region to simulate type-IV cracking. Finite element analysis was conducted to simulate multiaxiality in welded joints and to compare experimental results. The constitutive behavior for these materials is described by a power-law creep model. C and Q parameters are used to evaluate CCG rate of P92 welds for comparison. C parameters can characterize approximately 20% of the total life of CCG in P92 welds, and Q parameters can characterize approximately 80% of the total life. Q parameter is one of the useful parameters to predict CCG life in P92 welds.

1.
Fujita
,
T.
,
Asakura
,
K.
,
Sawada
,
T.
,
Takamatsu
,
T.
, and
Otoguro
,
Y.
, 1981, “
Creep Rupture Strength and Microstructure of Low C–10Cr–2Mo Heatresisting Steels With V and Nb
,”
Metall. Trans. A
0360-2133,
12A
, pp.
1071
1079
.
2.
Bell
,
K.
, 1997, “
Elevated Temperature Midlife Weldment Cracking (Type IV)—A Review
,” TWI Report No. 597.
3.
Elllis
,
F. V.
, and
Viswanathan
,
R.
, 1998, “
Review of Type IV Cracking
,” ASME PVP-Vol.
380
, pp.
59
76
.
4.
Tabuchi
,
M.
,
Hongo
,
H.
,
Watanabe
,
T.
, and
Yokobori
,
A. T.
, Jr.
, 2008, “
Creep Crack Growth Analysis of Welded Joints for High Cr Heat Resisting Steel
,” ASTM Paper No. STP1480, pp.
93
101
.
5.
Hasegawa
,
Y.
,
Ohgami
,
M.
, and
Okamoto
,
Y.
, 1998, “
Creep Properties of Heat Affected Zone of Weld in W Containing 9–12% Chromium Creep Resistant Martensitic Steels at Elevated Elevated Temperature
,”
Proceedings of Advanced Heat Resisting Steels for Power Generation
, San Sebastian, Spain.
6.
Sugiura
,
R.
,
Yokobori
,
A. T.
, Jr.
,
Tabuchi
,
M.
, and
Yokobori
,
T.
, 2007, “
Comparison of Creep Crack Growth Rate in Heat Affected Zone of Welded Joint for 9%Cr Ferritic Heat Resistant Steel Based on C∗, da/dt, K and Q∗ Parameters
,”
Eng. Fract. Mech.
0013-7944,
74
, pp.
868
881
.
7.
Nikbin
,
K. M.
,
Smith
,
D. J.
, and
Webster
,
G. A.
, 1984, “
'Prediction of Creep Crack Growth From Uniaxial Creep Data’
,”
Proc. R. Soc. London, Ser. A
0950-1207,
396
, pp.
183
197
.
8.
Riedel
,
H.
, and
Rice
,
J. R.
, 1980, “
Tensile Cracks in Creeping Solids
,”
Proceedings of the 12th Fracture Mechanics Conference
,
American Society for Testing Materials
,
Philadelphia, PA
, pp.
112
130
.
9.
Shih
,
C. F.
, 1983, “
Singular Field Quantities
,” Brown University Technical Report No. MRL E-147.
10.
Webster
,
G. A.
, and
Ainsworth
,
R. A.
, 1994,
High Temperature Component Life Assessment
, 1st ed.,
Chapman and Hall
,
London
.
11.
Davis
,
C. M.
,
Kourmpetis
,
M.
,
O’Dowd
,
N. P.
, and
Nikbin
,
K. M.
, 2007, “
Experimental Evaluation of the J or C∗ Parameter for a Range of Cracked Geometries
,” ASTM
STP1480
, pp.
321
340
.
12.
2007, “
ASTM E 1457-07: Standard Test Method for Measurement of Creep Crack Growth Times in Metals
,”
Annual Book of ASTM Standards
,
ASTM
,
Philadelphia, PA
, Vol.
3
.
13.
Bassani
,
J. L.
, and
McClintock
,
F. L.
, 1981, “
Creep Relaxation of Stress Around a Crack Tip
,”
Int. J. Solids Struct.
0020-7683,
17
, pp.
79
89
.
14.
Saxena
,
A.
, 1986, “
Creep Crack Growth Under Nonsteady-State Conditions
,”
Fracture Mechanics
,
American Society for Testing Materials
,
Philadelphia, PA
, Vol.
7
, pp.
185
201
.
15.
Ehlers
,
R.
, and
Riedel
,
H.
, 1991, “
A Finite Element Analysis of Creep Deformation in a Specimen Containing a Macroscopic Crack
,”
Advances in Fracture Research
,
D.
Francois
, ed.,
Pergamon
,
New York
, Vol.
2
, pp.
691
698
.
16.
Saxena
,
A.
, 1997,
Nonlinear Fracture Mechanics for Engineering
,
CRC
,
Boca Raton, FL
.
17.
Yokobori
,
A. T.
, Jr.
,
Yokobori
,
T.
,
Tomizawa
,
H.
, and
Sakata
,
H.
, 1983, “
Parametric Representation of Crack Growth Rate Under Creep, Fatigue and Creep-Fatigue Interaction at High Temperatures
,”
ASME J. Eng. Mater. Technol.
0094-4289,
105
, pp.
13
15
.
18.
Yokobori
,
A. T.
, Jr.
,
Yokobori
,
T.
,
Kuriyama
,
T.
,
Kato
,
T.
, and
Kaji
,
Y.
, 1986, “
Characterization of High Temperature Creep Crack Growth Rate in Terms of Independent Parameters
,”
Proceedings of the JSME/IME/ASME/ASTM International Conference on Creep
, pp.
135
140
.
19.
Yokobori
,
A. T.
, Jr.
, and
Yokobori
,
T.
, 1989, “
New Concept to Crack Growth at High Temperature Creep and Fatigue
,”
Advanced in Fracture Research, Proceedings of the Seventh International Conference on Fracture
,
Pergamon
,
New York
, pp.
1723
1735
.
20.
Yokobori
,
T.
,
Sakata
,
H.
, and
Yokobori
,
A. T.
, Jr.
, 1980, “
A New Parameter for Prediction of Creep Crack Growth Rate at High Temperature
,”
Eng. Fract. Mech.
0013-7944,
13
, pp.
533
539
.
21.
Yokobori
,
A. T.
, Jr.
,
Yokobori
,
T.
, and
Nishihara
,
T.
, 1991, “
Characterization of High Temperature Creep Crack Growth and Creep Life From High Temperature Ductile Through to High Temperature Brittle Materials
,”
Eng. Fract. Mech.
0013-7944,
40
, pp.
737
748
.
22.
Yokobori
,
A. T.
, Jr.
,
Uesugi
,
T.
,
Yokobori
,
T.
,
Fuji
,
A.
,
Kitagawa
,
M.
,
Yamaya
,
I.
,
Tabuchi
,
M.
, and
Yagi
,
K.
, 1998, “
Estimation of Creep Crack Growth Rate in IN-100 Based on the Q∗ Parameter Concept
,”
J. Mater. Sci.
0022-2461,
33
, pp.
1555
1562
.
23.
Sugiura
,
R.
,
Yokobori
,
A. T.
,
Takamori
,
S.
,
Tabuchi
,
M.
,
Fuji
,
A.
,
Yoda
,
M.
,
Kobayashi
,
K.
, and
Yokobori
,
T.
, 2006, “
Effects of Alloying Additions and Material Structures on the High Accuracy of the Predictive Law of Creep Crack Growth for W Strengthened 9–12% Ferritic Heat Resistant Steel
,”
J. Jpn. Inst. Met.
0021-4876,
70
(
5
), pp.
452
460
.
24.
JIS G 0567, 1998, “
Method of Elevated Temperature Tensile Test for Steels and Heat-Resisting Alloys
.”
25.
2007, “
ASTM E 139-06: Standard Test Methods for Conducting Creep, Creep-Rupture, and Stress-Rupture Tests of Metallic Materials
,”
Annual Book of ASTM Standards
,
ASTM
,
Philadelphia, PA
, Vol.
3
.
26.
Johnson
,
H. H.
, 1965, “
Calibrating the Electrical Potential Method for Studying Slow Crack Length
,”
Mater. Res. Stand.
0025-5394,
5
(
9
), pp.
442
445
.
27.
2004,
ABAQUS Version 6.3
,
Hibbitt, Karlsson & Sorensen, Inc.
,
USA
.
28.
Kimmins
,
S. T.
,
Coleman
,
M. C.
, and
Smith
,
D. J.
, 1993, “
An Overview of Creep Failure Associated With Heat Affected Zone of Ferritic Weldments
,”
Proceeding of the Fifth International Conference on Creep and Fatigue of Engineering Materials and Structure
,
B.
Wilshire
and
R. W.
Evans
, eds., Swansea.
29.
Perrin
,
I. J.
, and
Hayhurst
,
D. R.
, 1999, “
Continuum Damage Analysis of Type IV Creep Failure in Ferritic Steel Crosswelded Specimens
,”
Int. J. Pressure Vessels Piping
0308-0161,
76
, pp.
599
617
.
30.
Rice
,
J. R.
, and
Tracey
,
D. M.
, 1969, “
On the Ductile Enlargement of Voids in Triaxial Stress Fields
,”
J. Mech. Phys. Solids
0022-5096,
17
, pp.
201
217
.
31.
Cocks
,
A. C. F.
, and
Ashby
,
M. F.
, 1980, “
Intergranular Fracture in Power Law Creep Under Multiaxial Stress
,”
Met. Sci.
0306-3453,
14
, pp.
395
402
.
32.
Kim
,
Y. J.
, and
Schwalbe
,
K. -H.
, 2001, “
Mismatch Effect on Plastic Yield Load in Idealised Weldments II. Heat Affected Zone Cracks
,”
Eng. Fract. Mech.
0013-7944,
68
, pp.
183
199
.
33.
Song
,
T. K.
,
Kim
,
Y. J.
,
Kim
,
J. S.
, and
Jin
,
T. E.
, 2007, “
Mismatch Limit Loads and Approximate J Estimates for Tensile Plates With Constant-Depth Surface cracks in the center of Welds
,”
Int. J. Fract.
0376-9429,
148
, pp.
343
360
.
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