The changing face of power generation and the increasingly severe conditions experienced by power plant materials require an improved understanding of the deformation and failure response of power plant materials. Important insights can be obtained through computational studies, where the material microstructure is explicitly modeled. In such models, the physical mechanisms of deformation and damage can be represented at the microscale, providing a more accurate prediction of material performance. In this paper, two approaches are examined to represent the microstructure of a martensitic power plant steel (P91). In one approach, the model is based on a “measured microstructure” with electron backscatter diffraction (EBSD) employed to obtain the orientation of the martensitic grain structure of the steel. The alternative approach is to use a “numerically simulated” model where the microstructure is generated using the Voronoi tessellation method. In both cases, the microstructural model is incorporated within a representative volume element (RVE) in a finite-element analysis. The material constitutive response is represented by a nonlinear, rate dependent, finite strain crystal plasticity model, with the microstructural orientation specified at each finite-element integration point by the microstructural model. The predictions from the two approaches are compared. The stress distributions are observed to be very similar, though some differences are seen in the strain variation within the RVE.

References

References
1.
Shibli
,
A.
, and
Starr
,
F.
,
2007
, “
Some Aspects of Plant and Research Experience in the Use of New High Strength Martensitic Steel P91
,”
Int. J. Pressure Vessels Piping
,
84
(
1
), pp.
114
122
.10.1016/j.ijpvp.2006.11.002
2.
Brett
,
S. J.
,
Allen
,
D. J.
, and
Pacey
,
J.
,
1999
, “
Failure of a Modified 9Cr Header Endplate
,”
Case Histories on Integrity and Failures in Industry
,
V.
Bicego
,
A.
Nitta
,
J. W. H.
Price
, and
R.
Viswanathan
, eds., pp.
837
884
.
3.
Cipolla
,
L.
,
Di
Gianfrancesco
,
A.
,
Cumino
,
G.
,
Caminada
,
S.
, and
European Creep Collaborative Committee
,
2005
, “
Long Term Creep Behaviour and Microstructural Evolution of E911 Steel
,” Creep and Fracture in High Temperature Components: Design and Life Assessment Issues, p.
288
.
4.
Kitahara
,
H.
,
Ueji
,
R.
,
Tsuji
,
N.
, and
Minamino
,
Y.
,
2006
, “
Crystallographic Features of Lath Martensite in Low-Carbon Steel
,”
Acta Mater.
,
54
(
5
), pp.
1279
1288
.10.1016/j.actamat.2005.11.001
5.
Kitahara
,
H.
,
Ueji
,
R.
,
Ueda
,
M.
,
Tsuji
,
N.
, and
Minamino
,
Y.
,
2005
, “
Crystallographic Analysis of Plate Martensite in Fe–28.5 at.% Ni by FE-SEM/EBSD
,”
Mater. Charact.
,
54
(
4
), pp.
378
386
.10.1016/j.matchar.2004.12.015
6.
Gupta
,
G.
,
Was
,
G.
, and
Alexandreanu
,
B.
,
2004
, “
Grain Boundary Engineering of Ferritic-Martensitic Alloy T91
,”
Metall. Mater. Trans. A
,
35
(
2
), pp.
717
719
.10.1007/s11661-004-0382-3
7.
Maruyama
,
K.
,
Sawada
,
K.
, and
Koike
,
J.
,
2001
, “
Strengthening Mechanisms of Creep Resistant Tempered Martensitic Steel
,”
ISIJ Int.
,
41
(
6
), pp.
641
653
.10.2355/isijinternational.41.641
8.
Sauzay
,
M.
,
2009
, “
Modelling of the Evolution of Micro-Grain Misorientations During Creep of Tempered Martensite Ferritic Steels
,”
Mater. Sci. Eng., A
,
510
, pp.
74
80
.10.1016/j.msea.2008.04.121
9.
Czyrska-Filemonowicz
,
A.
,
Zielińska-Lipiec
,
A.
, and
Ennis
,
P.
,
2006
, “
Modified 9% Cr Steels for Advanced Power Generation: Microstructure and Properties
,”
J. Achiev. Mater. Manuf. Eng.
,
19
(
2
), pp.
43
48
. Available at http://w.journalamme.org/papers_vol19_2/1309.pdf
10.
Li
,
D.-F.
, and
O'Dowd
,
N. P.
,
2012
, “
Investigating Ductile Failure at the Microscale in Engineering Steels: A Micromechanical Finite Element Model
,”
Proceedings of 2012 ASME Pressure Vessels and Piping Division Conference
, pp.
137
143
.
11.
Li
,
D.-F.
, and
O'Dowd
,
N. P.
,
2011
, “
On the Evolution of Lattice Deformation in Austenitic Stainless Steels—The Role of Work Hardening at Finite Strains
,”
J. Mech. Phys. Solids
,
59
(
12
), pp.
2421
2441
.10.1016/j.jmps.2011.09.008
12.
Li
,
D. F.
,
Golden
,
B. J.
, and
O'Dowd
,
N. P.
,
2013
, “
Modelling of Micro-Plasticity Evolution in Crystalline Materials
,”
Proceedings of 2013 ASME Pressure Vessels and Piping Division Conferenc
e
.
13.
Dassault Systèmes Simulia Corp.
,
2011
, abaqus V6.11. Providence, RI.
14.
Meissonnier
,
F. T.
,
Busso
,
E. P.
, and
O'Dowd
,
N. P.
,
2001
, “
Finite Element Implementation of a Generalised Non-Local Rate-Dependent Crystallographic Formulation for Finite Strains
,”
Int. J. Plast.
,
17
(
4
), pp.
601
640
.10.1016/S0749-6419(00)00064-4
15.
matlab V7.1.
,
2005
,
The MathWorks, Inc.
,
Natick, MA
.
You do not currently have access to this content.