Low Cycle Fatigue Damage in Pressure-Vessel Materials

1963 ◽  
Vol 85 (4) ◽  
pp. 539-545 ◽  
Author(s):  
J. G. Sessler ◽  
Volker Weiss
Keyword(s):  
Pressure Vessel ◽  
Low Cycle Fatigue ◽  
Fatigue Tests ◽  
Cycle Fatigue ◽  
Property Changes ◽  
Failure Life ◽  
Damage Processes ◽  
The Relationship ◽  
Mean Strain ◽  
Strain Cycling

Strain-controlled tension-compression fatigue tests were performed on the ASTM pressure vessel steels, A302 and A225, to study the damage processes that lead to failure in low cycle fatigue. The measurements of static property changes in partially cycled specimens, and hysteresis loop effects obtained during cycling, were utilized to reflect the pattern of damage accumulation. In addition, strain cycling tests were conducted on these materials to assess the applicability of the relationship Nf=εF−ε0εTR2 as proposed by Manson [4] and Coffin [5] and modified by Sachs, et al. [6]. The experimental data obtained were in good agreement with the failure life and the effect of mean strain as predicted by the foregoing equation. Accordingly, a positive mean strain (prestrain in tension) reduces fatigue life, since the fracture strain available for cycling is reduced by the amount of the prestrain. The damage studies indicated, however, that this equation cannot be used to describe the progress of damage during strain cycling. Rather, it appears that damage is governed by at least two, possibly interdependent, processes; namely, the loss of available ductility due to strain hardening and the formation and growth of cracks which finally determine failure. Both processes are reflected in the remaining ductility after partial cycling. At present, it is not clear how the two processes combine to yield the experimentally confirmed relationship, Nf=εF−ε0εTR2.

Effect of Creep in Low-Cycle Fatigue of Pressure Vessel Steel

1970 ◽  
Vol 92 (1) ◽  
pp. 67-73 ◽  
Author(s):  
J. Dubuc ◽  
A. Biron
Keyword(s):  
Pressure Vessel ◽  
Low Cycle Fatigue ◽  
Strain Range ◽  
Fatigue Tests ◽  
Pressure Vessel Steel ◽  
Cycle Fatigue ◽  
Total Strain Range ◽  
Vessel Steel ◽  
The Mean ◽  
Mean Strain

Low-cycle fatigue tests have been carried out at 2 cpm on a pressure vessel steel at 350 deg C (662 deg F). The total strain range was fixed for each test and the minimum (or mean) strain in some cases was constant (zero minimum value), in others increased uniformly in time at a predetermined rate. It was found that variations in the mean strain up to 0.5 percent/hour had no significant influence on the results.

Effect of Mean Stress and of Mean Strain in Low-Cycle Fatigue of A-517 and A-201 Steels

1970 ◽  
Vol 92 (1) ◽  
pp. 35-51 ◽  
Author(s):  
J. Dubuc ◽  
J. R. Vanasse ◽  
A. Biron ◽  
A. Bazergui
Keyword(s):  
Plastic Strain ◽  
Pressure Vessel ◽  
Room Temperature ◽  
Low Cycle Fatigue ◽  
Fatigue Tests ◽  
Mean Stress ◽  
Cycle Fatigue ◽  
The Mean ◽  
Mean Strain

A number of low-cycle fatigue tests has been carried out at room temperature on two materials commonly used in pressure vessel fabrication. For strain-controlled tests, the influence of different mean strains is studied; similarly, the effect of varying the mean stress is analyzed for stress-controlled tests. Relations involving elastic and plastic strain ranges, and the variations of strains or stresses during the fatigue tests are discussed.

Cumulative Damage and Effect of Mean Strain in Low-Cycle Fatigue of a 2024-T351 Aluminum Alloy

1966 ◽  
Vol 88 (4) ◽  
pp. 801-810 ◽  
Author(s):  
Kiyotsugu Ohji ◽  
W. R. Miller ◽  
Joseph Marin
Keyword(s):  
Aluminum Alloy ◽  
Fatigue Life ◽  
Low Cycle Fatigue ◽  
Cumulative Damage ◽  
Strain Condition ◽  
Cycle Fatigue ◽  
History Of ◽  
Mean Strain ◽  
Strain Cycling ◽  
Cycling Behavior

By assuming a linear cumulative damage hypothesis for strain cycling, theories are developed in this paper for fatigue life under varying strain amplitude, residual ductility after a given history of strain cyling, and life under mean strain condition. These predictions are based on uniaxial completely reversed cycling behavior. The expressions obtained were compared with the experimental results on 2024-T351 aluminum alloy as well as other data available in the literature. The agreements between theories and experiments were found to be satisfactory.

Low Cycle Fatigue Study of 63Sn-37Pb Solder under Torsional Cyclic Loading

2013 ◽  
Vol 785-786 ◽  
pp. 72-75
Author(s):  
Hong Qiang Guo
Keyword(s):  
Experimental Data ◽  
Low Cycle Fatigue ◽  
Constant Strain Rate ◽  
Fatigue Tests ◽  
Stress And Strain ◽  
Cycle Fatigue ◽  
Fatigue Lifetime ◽  
Torsional Fatigue ◽  
Relationship Of ◽  
The Relationship

In this paper, the torsional fatigue tests under angle control at the constant strain rate of 5×10-3/s were conducted on 63Sn–37Pb solder over a range of . The relationship of stress and strain for the 63Sn–37Pb solder was investigated. The number of cycle with loading decrease of 25% was thought as the fatigue lifetime. The parameters of Coffin-Manson equation were determined based on the experimental data.

scholarly journals INVESTIGATION OF THE CONSTRUCTION OF PROBABILISTIC LOW CYCLE FATIGUE DESIGN CURVES AT STRAIN CYCLING

Transport ◽  
2005 ◽  
Vol 20 (5) ◽  
pp. 195-203 ◽  
Author(s):  
Žilvinas Bazaras
Keyword(s):  
Aluminium Alloy ◽  
Mechanical Characteristics ◽  
Low Cycle Fatigue ◽  
Fracture Probability ◽  
Fatigue Tests ◽  
Probabilistic Methods ◽  
Cycle Fatigue ◽  
Fatigue Design ◽  
Cycle Loading ◽  
Strain Cycling

Probabilistic methods are based on the use of statistical data about mechanical characteristics and lifetime at cyclic loading of a material. In this investigation statistical low cycle fatigue tests were carried out and mechanical characteristics of three materials (steel of grades 15X2MFA and 45 and aluminium alloy D16T1), representing all possible variations of cyclic properties (fatigue, quasi ‐ static and intermediate mode of fracture) were determined experimentally. Based on the obtained data the analysis of design curves of equal fracture probability for steels 15X2MFA and 45 and aluminium alloy D16T1 at strain low cycle loading was performed and the design curves were compared with the experimental ones.

Cyclic Stress-Strain Behavior and Low-Cycle Fatigue of Ti 6-4 at 260°C

1992 ◽  
Vol 114 (4) ◽  
pp. 390-398 ◽  
Author(s):  
T. Bui-Quoc ◽  
R. Gomuc ◽  
A. Biron
Keyword(s):  
Strain Amplitude ◽  
Low Cycle Fatigue ◽  
Strain Curve ◽  
Cyclic Stress ◽  
Fatigue Tests ◽  
Cycle Fatigue ◽  
Stress Strain ◽  
Strain Behavior ◽  
Show Evidence ◽  
Strain Cycling

Low-cycle fatigue tests on Ti 6-4 (Ti-6Al-4V) have been carried out at 260°C under strain-controlled conditions with constant strain amplitude and increasing multistep strain levels. The results of constant strain amplitude tests were used to establish the fatigue diagram whereas the multistep tests were examined to assess the cyclic stress-strain behavior in comparison with the conventional stress-strain curve. Most of the tests were carried out under zero-to-tension conditions in the intermediatecycle range (Nf ≃ 3 x 103 to 105 cycles). The effect of prior strain cycling on the tensile properties was also investigated. The experimental data is discussed together with theoretical evaluations. In addition, microstructural examinations of the rupture surfaces have been made to show evidence on the type of crack initiation sites and on the crack propagation modes at different strain levels.

Interactive Mechanisms of Sulfide Inclusions and Environmental Factors in Low Cycle Fatigue Process of Pressure Vessel Steels in High Temperature Water

2005 ◽  
Vol 475-479 ◽  
pp. 253-256
Author(s):  
Xin Qiang Wu
Keyword(s):  
High Temperature ◽  
Pressure Vessel ◽  
Low Cycle Fatigue ◽  
Fatigue Cracking ◽  
Cyclic Stress ◽  
Fatigue Tests ◽  
Cycle Fatigue ◽  
High Temperature Water ◽  
Pressure Vessel Steels ◽  
Temperature Water

Low cycle fatigue tests were conducted in high temperature water for A533B pressure vessel steels with sulfur contents of 0.013, 0.025 and 0.038 wt.% respectively. Cyclic stress amplitude response and fatigue resistance as well as influence of strain rate, temperature and dissolved oxygen concentration in water were investigated. Fatigue cracking/fractograhpic features were examined. Sulfide-related environmentally assisted cracking mechanism is discussed.

scholarly journals Fatigue Testing of Wearable Sensing Technologies: Issues and Opportunities

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4070
Author(s):  
Andrea Karen Persons ◽  
John E. Ball ◽  
Charles Freeman ◽  
David M. Macias ◽  
Chartrisa LaShan Simpson ◽  
...  
Keyword(s):  
Fatigue Life ◽  
Prediction Models ◽  
Fatigue Testing ◽  
Low Cycle Fatigue ◽  
Wearable Sensors ◽  
Fatigue Tests ◽  
Proof Of Concept ◽  
Cycle Fatigue ◽  
Wearable Sensing ◽  
Failure Data

Standards for the fatigue testing of wearable sensing technologies are lacking. The majority of published fatigue tests for wearable sensors are performed on proof-of-concept stretch sensors fabricated from a variety of materials. Due to their flexibility and stretchability, polymers are often used in the fabrication of wearable sensors. Other materials, including textiles, carbon nanotubes, graphene, and conductive metals or inks, may be used in conjunction with polymers to fabricate wearable sensors. Depending on the combination of the materials used, the fatigue behaviors of wearable sensors can vary. Additionally, fatigue testing methodologies for the sensors also vary, with most tests focusing only on the low-cycle fatigue (LCF) regime, and few sensors are cycled until failure or runout are achieved. Fatigue life predictions of wearable sensors are also lacking. These issues make direct comparisons of wearable sensors difficult. To facilitate direct comparisons of wearable sensors and to move proof-of-concept sensors from “bench to bedside,” fatigue testing standards should be established. Further, both high-cycle fatigue (HCF) and failure data are needed to determine the appropriateness in the use, modification, development, and validation of fatigue life prediction models and to further the understanding of how cracks initiate and propagate in wearable sensing technologies.

Cumulative acoustic emission energy for damage detection in composites reinforced by carbon fibers within low-cycle fatigue regime at various displacement amplitudes and rates

2021 ◽  
pp. 096739112098570
Author(s):  
Mohammad Azadi ◽  
Mohsen Alizadeh ◽  
Seyed Mohammad Jafari ◽  
Amin Farrokhabadi
Keyword(s):  
Acoustic Emission ◽  
Carbon Fibers ◽  
Polymer Matrix Composites ◽  
Low Cycle Fatigue ◽  
Energy Parameter ◽  
Fatigue Tests ◽  
Matrix Cracking ◽  
Matrix Composites ◽  
Cycle Fatigue ◽  
Cumulative Energy

In the present article, acoustic emission signals were utilized to predict the damage in polymer matrix composites, reinforced by carbon fibers, in the low-cycle fatigue regime. Displacement-controlled fatigue tests were performed on open-hole samples, under different conditions, at various displacement amplitudes of 5.5, 6.0, 6.5 and 7.0 mm and also under various displacement rates of 25, 50, 100 and 200 mm/min. After acquiring acoustic emission signals during cycles, two characteristic parameters were used, including the energy and the cumulative energy. Obtained results implied that the energy parameter of acoustic emission signals could be used only for the macroscopic damage, occurring at more than 65% of normalized fatigue cycles under different test conditions. However, the cumulative energy could properly predict both microscopic and macroscopic defects, at least two failure types, including matrix cracking at first cycles and the fiber breakage at last cycles. Besides, scanning electron microscopy images proved initially such claims under all loading conditions.

Fatigue and Burst Analysis of Hy-140(T) Steel Pressure Vessels

1970 ◽  
Vol 92 (1) ◽  
pp. 11-16 ◽  
Author(s):  
J. M. Barsom ◽  
S. T. Rolfe
Keyword(s):  
Yield Strength ◽  
Pressure Vessel ◽  
Low Cycle Fatigue ◽  
High Strength Steels ◽  
High Strength ◽  
Fatigue Tests ◽  
Pressure Vessels ◽  
High Yield ◽  
Corrosion Properties ◽  
Burst Analysis

Increasing use of high-strength steels in pressure-vessel design has resulted from emphasis on decreasing the weight of pressure vessels for certain applications. To demonstrate the suitability of a 140-ksi yield strength steel for use in unwelded pressure vessels, HY-140(T)—a quenched and tempered 5Ni-Cr-Mo-V steel—was fabricated and subjected to various burst and fatigue tests, as well as to various laboratory tests. In general, results of the investigation indicated very good tensile, Charpy, Nil Ductility Transition Temperature (NDT), low-cycle fatigue, and stress-corrosion properties of HY-140(T) steels, as well as very good burst tests results, in comparison with existing high-yield strength pressure-vessel steels. The results also indicate that the HY-140(T) steel should be an excellent material for its originally designed purpose, Naval hull applications.

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