Room-temperature fatigue tests were conducted on Ti 834 with prior creep strains accumulated under constant load at 550 °C and 600 °C, respectively. Microstructural and fractographic examinations on specimens with prior creep strain > 3% revealed the failure process consisting of multiple surface crack nucleation and internal void generation by creep, followed by fatigue crack propagation in coalescence with the internally distributed damage, leading to the final fracture. The amount of prior creep damage increased with creep strain. The fatigue life of Ti 834 was significantly reduced by prior creep straining. The behavior is rationalized with the integrated creep-fatigue theory.

References

References
1.
Es-Souni
,
M.
,
2001
, “
Creep Behaviour and Creep Microstructures of a High-Temperature Titanium Alloy Ti–5.8Al–4.0Sn–3.5Zr–0.7Nb–0.35Si–0.06C (Timetal 834)—Part I: Primary and Steady-State Creep
,”
Mater. Charact.
,
46
(
5
), pp.
365
379
.
2.
Potozky
,
P.
,
Maier
,
H. J.
, and
Christ
,
H.-J.
,
1998
, “
Thermomechanical Fatigue Behavior of the High Temperature Titanium Alloy IMI 834
,”
Metall. Mater. Trans. A
,
29
(
12
), pp.
2995
3004
.
3.
Kordisch
,
T.
, and
Nowack
,
H.
,
1998
, “
Life Prediction for the Titanium Alloy IMI 834 Under High Temperature Creep-Fatigue Loadings
,”
Fatigue Fract. Eng. Mater. Struct.
,
21
(
1
), pp.
47
63
.
4.
Maier
,
H. J.
,
1998
, “
High-Temperature Fatigue of Titanium Alloys
,”
Mater. High Temp.
,
15
(
1
), pp.
3
14
.
5.
Ghonem
,
H.
, and
Foerch
,
R.
,
1991
, “
Frequency Effects on Fatigue Crack Growth Behavior in a Near—A Titanium Alloy
,”
Mater. Sci. Eng. A
,
138
(
1
), pp.
69
81
.
6.
Parida
,
B. K.
, and
Nicholas
,
T.
,
1994
, “
Elevated Temperature Fatigue Crack Growth Behavior of Ti-1100
,”
Fatigue Fract. Eng. Mater. Struct.
,
17
(
5
), pp.
551
561
.
7.
Hardt
,
S.
,
Maier
,
H. J.
, and
Christ
,
H.-J.
,
1999
, “
High-Temperature Fatigue Damage Mechanisms in Near-α Titanium Alloy IMI 834
,”
Int. J. Fatigue
,
21
(
8
), pp.
779
789
.
8.
Spindler
,
M. W.
,
2007
, “
An Improved Method for Calculation of Creep Damage During Creep–Fatigue Cycling
,”
Mat. Sci. Tech.
,
23
(
12
), pp.
1461
1470
.
9.
Wu
,
X. J.
,
2009
, “
A Model of Nonlinear Fatigue-Creep (Dwell) Interactions
,”
ASME J. Eng. Gas Turbines Power
,
131
(
3
), p.
032101
.
10.
Wu
,
X. J.
,
2015
, “
An Integrated Creep-Fatigue Theory for Material Damage Modeling
,”
Key Eng. Mater.
,
627
, pp.
341
344
.
You do not currently have access to this content.