Combined effect of residual and mean stresses on fatigue behavior of welded aluminum 2024 alloy

Abstract Low cycle fatigue (LCF) tests of type 316 stainless steel (SS) were conducted in simulated pressurized water reactor (PWR) environments to evaluate the effect of zinc (Zn) content and peak strain holding. The LCF lives of 316 SS increased about 2 to 3 times in PWR environments with Zn addition and peak strain holding (Zn-PWRhold condition). Their combined effect was investigated by using cyclic hardening behavior, dislocation structure analysis, and oxide layer observation. The cyclic behavior in Zn-PWRhold condition showed general primary hardening behavior but quite longer softening behavior than other test conditions. Also, the dislocation density was decreased with Zn addition and increased again with peak strain holding. The Zn penetrates into the oxide layer at the crack tip and modifies the oxide characteristics, which results in improvement of corrosion resistance.

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The fatigue behavior of composite laminates under various mean stresses

Composite Structures ◽

10.1016/0263-8223(91)90065-7 ◽

1991 ◽

Vol 17 (2) ◽

pp. 113-126 ◽

Cited By ~ 13

Author(s):

A. Rotem

Keyword(s):

Composite Laminates ◽

Fatigue Behavior ◽

Mean Stresses

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Correlation between Dislocation Structures and Mechanical Fatigue Response of 316L Austenitic Steel Loaded with and without Mean Stress at High Temperature in Air and Water Environment

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.258.534 ◽

2016 ◽

Vol 258 ◽

pp. 534-537 ◽

Cited By ~ 1

Author(s):

Milan Heczko ◽

Philippe Spätig ◽

Hans Peter Seifert ◽

Tomáš Kruml

Keyword(s):

Fatigue Behavior ◽

Water Environment ◽

Cyclic Stress ◽

Mean Stress ◽

Mechanical Fatigue ◽

Transmission Electron ◽

316L Austenitic Stainless Steel ◽

Dissolved Hydrogen ◽

Means Of Transmission ◽

Mean Stresses

Load-controlled experiments were conducted to study the influence of mean stress on the fatigue behavior of 316L austenitic stainless steel at the temperature of 288°C in air and light water reactor (LWR) conditions. Water environment was characterized by high-purity, neutral water with 150 ppb dissolved hydrogen. The internal dislocation structures of the material were investigated by means of transmission electron microscopy (TEM). The formation of dislocation structures for different loading conditions and different mean stresses was assessed and discussed in relation to the cyclic stress-strain response of the material as well as the effects of non-zero mean stress conditions. All findings were considered to discuss the fatigue softening/hardening behavior and the influence of mean stress on the fatigue life of material in the LWR environment.

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On the in vitro Fatigue Behavior of Human Dentin: Effect of Mean Stress

Journal of Dental Research ◽

10.1177/154405910408300305 ◽

2004 ◽

Vol 83 (3) ◽

pp. 211-215 ◽

Cited By ~ 50

Author(s):

R.K. Nalla ◽

J.H. Kinney ◽

S.J. Marshall ◽

R.O. Ritchie

Keyword(s):

Fatigue Failure ◽

Fatigue Behavior ◽

Load Ratio ◽

Fatigue Loading ◽

Cyclic Fatigue ◽

R Ratio ◽

Wide Range ◽

Human Dentin ◽

Mean Stresses

Human dentin is susceptible to failure under repetitive cyclic-fatigue loading. This investigation seeks to address the paucity of data that reliably quantify this phenomenon. Specifically, the effect of alternating vs. mean stresses, characterized by the stress- or load-ratio R (ratio of minimum-to-maximum stress), was investigated for three R values (−1, 0.1, and 0.5). Dentin was observed to be prone to fatigue failure under cyclic stresses, with susceptibility varying, depending upon the stress level. The “stress-life” ( S/N) data obtained are discussed in the context of constant-life diagrams for fatigue failure. The results provide the first fatigue data for human dentin under tension-compression loading and serve to map out safe and unsafe regimes for failure over a wide range of in vitro fatigue lives (< 103 to > 106 cycles).

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Influence of static mean stresses on the fatigue behavior of 2024 aluminum alloy under multiaxial loading

Frattura ed Integrità Strutturale ◽

10.3221/igf-esis.51.12 ◽

2019 ◽

Vol 14 (51) ◽

pp. 151-163

Author(s):

Andrey Yankin ◽

Valerii Wildemann ◽

Nikolai Belonogov ◽

Oleg Staroverov

Keyword(s):

Aluminum Alloy ◽

Fatigue Behavior ◽

Multiaxial Loading ◽

2024 Aluminum Alloy ◽

Mean Stresses

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Fatigue Behavior of K447A Superalloy under Low Cycle Fatigue and Creep-Fatigue Interaction Conditions

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.750.121 ◽

2015 ◽

Vol 750 ◽

pp. 121-126 ◽

Cited By ~ 1

Author(s):

Hui Chen Yu ◽

Cheng Li Dong ◽

Ying Li

Keyword(s):

Fatigue Life ◽

Low Cycle Fatigue ◽

Fatigue Behavior ◽

Hold Time ◽

Strain Ratio ◽

Mean Stress ◽

Cycle Fatigue ◽

Creep Fatigue ◽

Cyclic Damage ◽

Mean Stresses

Strain-controlled low cycle fatigue (LCF) and creep-fatigue interaction (CFI) tests of K447A are conducted at 760oC in order to investigate the effects of different dwell times and strain ratios on the fatigue behavior and life. For the cases of stain ratio Rε=-1 with balanced hold time, the tensile and compressive mean stresses will generate. For the case of stain ratio Rε=-1 with compressive holding 60s, the tensile mean stress will produce. For the case of stain ratio Rε=-1 with tensile holding 60s, the compressive mean stress will produce. For the cases of stain ratio Rε=0.1 and Rε=-1with no hold time, the tensile mean stress will produce. The cyclic damage accumulation (CDA) method and modified CDA method were employed to predict the fatigue life for K447A, respectively. The fatigue life predicted by CDA method is within the scatter band of 18.2X. The fatigue life predicted by the modified CDA method agrees very well with the experimental life and the predicted life is well within the scatter band of 3.1X, which means that the modified CDA method is able to consider the influences of dwell time and strain ratio on the fatigue life of K447A.

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