Low Cycle Fatigue Behavior of a New Type of Zircaloy Material

To investigate the property of a new type of Zircaloy material, a low cycle fatigue (LCF) test has been performed at room temperature (RT) and 375°C. Results show that the new alloy generally displays cyclic hardening followed by a continuous softening behavior. Fatigue lifetime curves as a function of strain range imply that the new alloy has a nearly same lifetime than that of Zr-4 at RT, and superior than that at 375°C.

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Comparative Low-Cycle Fatigue Behavior of HAYNES 244 Alloy and Waspaloy

10.1115/gt2021-59619 ◽

2021 ◽

Author(s):

Michael G. Fahrmann

Keyword(s):

Thermal Loading ◽

Coefficient Of Thermal Expansion ◽

Low Cycle Fatigue ◽

Fatigue Behavior ◽

Axial Strain ◽

Fatigue Crack Initiation ◽

High Strength ◽

Cyclic Hardening ◽

Cycle Fatigue ◽

Softening Behavior

Abstract HAYNES® 244® alloy was chiefly developed to address the need for high-strength, low coefficient of thermal expansion (CTE) alloys for seal rings and cases in advanced gas turbine engines. In addition to these attributes, adequate resistance to low-cycle fatigue (LCF) due to cyclic thermal and mechanical loading during service is critical for such applications. The isothermal LCF performance of commercially produced 0.5” (12.5 mm) thick, fully heat treated plate products of 244 alloy was evaluated by means of axial strain-controlled (R = −1) LCF tests covering total strain ranges up to 1.25 % (without dwells), at temperatures ranging from 800–1400°F (427–760°C). In addition, the comparative LCF performance of Waspaloy, a well-established alloy for turbine cases, was evaluated under selected, nominally identical test conditions. S-N curves were constructed and fitted by the Coffin-Manson equation, allowing the delineation of regimes controlled by the elastic and plastic response of the material. Fracture surfaces were examined in the scanning electron microscope to identify fatigue crack initiation sites and crack propagation modes. Differences between the alloys are discussed in terms of tensile strength and cyclic hardening/softening behavior. Implications for fatigue performance of these alloys under cyclic thermal loading conditions are discussed as well.

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Low Cycle Fatigue of Alloy 617 at 850 °C and 950 °C

Journal of Engineering Materials and Technology ◽

10.1115/1.4023673 ◽

2013 ◽

Vol 135 (3) ◽

Cited By ~ 21

Author(s):

J. K. Wright ◽

L. J. Carroll ◽

J. A. Simpson ◽

R. N. Wright

Keyword(s):

Strain Rate ◽

Low Cycle Fatigue ◽

Fatigue Behavior ◽

Strain Range ◽

Cyclic Hardening ◽

Solute Drag ◽

Cycle Fatigue ◽

Alloy 617 ◽

Total Strain Range ◽

Cycles To Failure

The low cycle fatigue behavior of Alloy 617 has been evaluated at 850 °C and 950 °C, the temperature range of particular interest for the intermediate heat exchanger on a proposed high-temperature gas-cooled nuclear reactor. Cycles to failure were measured as a function of total strain range and varying strain rate. Results of the current experiments compare well with previous work reported in the literature for a similar range of temperatures and strain rate. The combined data demonstrate a Coffin–Manson relationship, although the slope of the Coffin–Manson fit is close to −1 rather than the typically reported value of −0.5. At 850 °C and a strain rate of 10−3 /s Alloy 617 deforms by a plastic flow mechanism in low cycle fatigue and exhibits some cyclic hardening. At 950 °C for strain rates of 10−3–10−5 /s, Alloy 617 deforms by a solute drag creep mechanism during low cycle fatigue and does not show significant cyclic hardening or softening. At this temperature the strain rate has little influence on the cycles to failure for the strain ranges tested.

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The low Cycle Fatigue Behavior of Three advanced Nickel-Base Eutectic Composites

MRS Proceedings ◽

10.1557/proc-12-59 ◽

1981 ◽

Vol 12 ◽

Author(s):

T. Ishii ◽

D. J. Duquette ◽

N. S. Stoloff

Keyword(s):

Plastic Strain ◽

Linear Relation ◽

Low Cycle Fatigue ◽

Fatigue Behavior ◽

Strain Range ◽

Cyclic Hardening ◽

Metals And Alloys ◽

Cycle Fatigue ◽

Plastic Strain Range ◽

Nickel Base

AbstractThe low cycle fatigue behavior at 25°C and 825°C of three advanced nickel-base eutectics is described. Fatigue lives are shown to obey a linear relation with plastic strain range (Coffin-Manson relation) but lives are much lower than are observed for conventional metals and alloys. Cyclic hardening and softening were observed in each alloy at 25 °C; however, this behavior differs from the classical saturation behavior observed with isotropic materials.

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Multiaxial Low Cycle Fatigue Life Prediction at 300 °C Using Equivalent Strain Appoach

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.361-363.1669 ◽

2011 ◽

Vol 361-363 ◽

pp. 1669-1672

Author(s):

Wen Xiao Zhang ◽

Guo Dong Gao ◽

Guang Yu Mu

Keyword(s):

Fatigue Life ◽

Life Prediction ◽

Low Cycle Fatigue ◽

Fatigue Behavior ◽

Strain Range ◽

Cyclic Fatigue ◽

Equivalent Strain ◽

Multiaxial Fatigue ◽

Fatigue Life Prediction ◽

Cycle Fatigue

The low cycle fatigue behavior was experimentally studied with the 3-dimension notched LD8 aluminum alloy specimens at 300°C. The 3- dimension stress-strain responses of specimens were calculated by means of the program ADINA. The multiaxial fatigue life prediction was carried out according to von Mises’s equivalent theory. The results from the prediction showed that the equivalent strain range can be served as the valid mechanics for predicting multiaxial high temperature and low cyclic fatigue life.

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Low cycle fatigue behavior of modified 9Cr–1Mo steel at room temperature

Materials Science and Engineering A ◽

10.1016/j.msea.2015.11.060 ◽

2016 ◽

Vol 652 ◽

pp. 30-41 ◽

Cited By ~ 30

Author(s):

Preeti Verma ◽

N.C. Santhi Srinivas ◽

S.R. Singh ◽

Vakil Singh

Keyword(s):

Room Temperature ◽

Low Cycle Fatigue ◽

Fatigue Behavior ◽

Cycle Fatigue

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High-Temperature Low-Cycle Fatigue Behavior of MarBN at 600 °C

Journal of Pressure Vessel Technology ◽

10.1115/1.4031724 ◽

2016 ◽

Vol 138 (4) ◽

Cited By ~ 8

Author(s):

Richard A. Barrett ◽

Eimear M. O'Hara ◽

Padraic E. O'Donoghue ◽

Sean B. Leen

Keyword(s):

High Temperature ◽

Low Cycle Fatigue ◽

Kinematic Hardening ◽

Fatigue Behavior ◽

Strain Range ◽

Material Model ◽

Cyclic Softening ◽

Cyclic Strength ◽

Cycle Fatigue ◽

Viscoplastic Material

This paper presents the high-temperature low-cycle fatigue (HTLCF) behavior of a precipitate strengthened 9Cr martensitic steel, MarBN, designed to provide enhanced creep strength and precipitate stability at high temperature. The strain-controlled test program addresses the cyclic effects of strain-rate and strain-range at 600 °C, as well as tensile stress-relaxation response. A recently developed unified cyclic viscoplastic material model is implemented to characterize the complex cyclic and relaxation plasticity response, including cyclic softening and kinematic hardening effects. The measured response is compared to that of P91 steel, a current power plant material, and shows enhanced cyclic strength relative to P91.

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Low Cycle Fatigue Behavior of AA2219-T87 at Room Temperature

Materials Performance and Characterization ◽

10.1520/mpc20130092 ◽

2014 ◽

Vol 3 (1) ◽

pp. 20130092 ◽

Cited By ~ 2

Author(s):

V. M. J. Sharma ◽

G. Sudarshan Rao ◽

S. C. Sharma ◽

Koshy M. George

Keyword(s):

Room Temperature ◽

Low Cycle Fatigue ◽

Fatigue Behavior ◽

Cycle Fatigue

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Low-cycle fatigue behavior of NIMONIC PE16 at room temperature

Metallurgical Transactions A ◽

10.1007/bf02656817 ◽

1991 ◽

Vol 22 (2) ◽

pp. 499-506 ◽

Cited By ~ 43

Author(s):

V. Singh ◽

M. Sundararaman ◽

W. Chen ◽

R. P. Wahi

Keyword(s):

Room Temperature ◽

Low Cycle Fatigue ◽

Fatigue Behavior ◽

Cycle Fatigue

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Low Cycle Fatigue Characteristics of a Low-Thermal Expansion, High Strength Alloy (HAYNES 242 Alloy)

Volume 4: Cycle Innovations; Fans and Blowers; Industrial and Cogeneration; Manufacturing Materials and Metallurgy; Marine; Oil and Gas Applications ◽

10.1115/gt2011-46817 ◽

2011 ◽

Author(s):

L. M. Pike ◽

S. K. Srivastava

Keyword(s):

Thermal Expansion ◽

Low Cycle Fatigue ◽

Fatigue Behavior ◽

Strain Range ◽

High Strength ◽

Wave Form ◽

Cycle Fatigue ◽

Total Strain Range ◽

Low Thermal Expansion ◽

Long Range Ordering

HAYNES® 242® alloy, based primarily on the Ni-25Mo-8Cr system, derives its low thermal expansion characteristics from its composition and its high strength concomitant with high ductility from a long-range ordering reaction upon an aging heat treatment. This combination has enabled the alloy continually to find a challenging range of applications in the aerospace industry at up to 1300°F (704°C). These include seal rings, containment rings, duct segments, casings, rocket nozzles, etc. In conjunction with the creep strength and environmental resistance, the low cycle fatigue (LCF) behavior is an important material property affecting the service life of 242 alloy components. The low cycle fatigue behavior of 242 alloy was studied under fully reversed strain-controlled mode at 800°F (427°C), 1000°F (538°C), 1200°F (649°C) and 1400°F (760°C) using a triangular wave form with a frequency of 0.33 Hz. Results are presented in terms of cycles to crack initiation and failure. The magnitudes of fatigue lives at total strain range ≤ 0.7% at 800, 1000 and 1200°F are significantly greater than those of solid solution strengthened alloys. Additionally, stress-controlled LCF tests were performed at 1200°F (649°C) on 242 alloy as well as 909 alloy (for comparison). The paper will discuss the results of these two test programs.

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