Damage Accumulation and Growth Models for the Creep-Fatigue Interaction

2020 ◽  
pp. 112-116
Author(s):  
A. V. Tumanov ◽  
V. N. Shlyannikov
Keyword(s):  
Damage Accumulation ◽  
Growth Models ◽  
Creep Fatigue

Probabilistic Prediction of Crack Growth Based on Creep/Fatigue Damage Accumulation Mechanism

2011 ◽  
Vol 8 (5) ◽  
pp. 103690 ◽  
Author(s):  
Zhigang Wei ◽  
Fulun Yang ◽  
Henry Cheng ◽  
Kamran Nikbin ◽  
A. Saxena ◽  
...  
Keyword(s):  
Crack Growth ◽  
Fatigue Damage ◽  
Damage Accumulation ◽  
Probabilistic Prediction ◽  
Fatigue Damage Accumulation ◽  
Creep Fatigue ◽  
Accumulation Mechanism

Bone creep-fatigue damage accumulation

1989 ◽  
Vol 22 (6-7) ◽  
pp. 625-635 ◽  
Author(s):  
William E. Caler ◽  
Dennis R. Carter
Keyword(s):  
Fatigue Damage ◽  
Damage Accumulation ◽  
Fatigue Damage Accumulation ◽  
Creep Fatigue

A New Linear Superposition Theory and its Application in Creep Fatigue-Oxidation Crack Growth Modeling

2012 ◽  
Author(s):  
Zhigang Wei ◽  
Fulun Yang ◽  
Burt Lin ◽  
Limin Luo ◽  
Dmitri Konson ◽  
...  
Keyword(s):  
Crack Growth ◽  
Growth Models ◽  
Worked Examples ◽  
Damage Mechanism ◽  
Turbine Engines ◽  
Linear Superposition ◽  
Creep Fatigue ◽  
Growth Laws ◽  
Cycle Dependent ◽  
Crack Growth Modeling

Fatigue, creep, oxidation or their combinations have long been recognized as the principal mechanisms in many high-temperature failures in power plant components, turbine engines, and exhaust systems in vehicles. Depending on the specific materials and loading conditions and temperature, the role of each damage mechanism may change significantly, ranging from independent development to competing and combined creep-fatigue, fatigue-oxidation, and creep-fatigue-oxidation. In this paper a new linear superposition theory is proposed to model the cycle-dependent and time-dependent creep-fatigue-oxidation crack growth phenomena. The model can be reduced to creep-fatigue and fatigue-oxidation crack growth models previously developed by the authors as well as, under some assumptions, the current widely used linear superposition theory. The limits of the current superposition theory and the advantages of the new theory are clearly demonstrated with several worked examples. A general probabilistic analysis procedure is also proposed by introducing the uncertainties of parameters in fatigue, creep, and oxidation crack growth laws with the help of the Monte Carlo simulation.

A Uniaxial Damage Accumulation Law for Time-Varying Loading Including Creep-Fatigue Interaction

1979 ◽  
Vol 101 (2) ◽  
pp. 118-124 ◽  
Author(s):  
W. J. Ostergren ◽  
E. Krempl
Keyword(s):  
Damage Accumulation ◽  
Low Cycle Fatigue ◽  
304 Stainless Steel ◽  
Fatigue Data ◽  
Creep Fatigue ◽  
Sequence Effects ◽  
Tension And Compression ◽  
Type 304 ◽  
Type 304 Stainless Steel ◽  
Special Case

A differential form for damage accumulation is proposed wherein the rate of damage accumulation is equal to a product of two functions. The first depends only on the present damage and the second has the present value of the controlled quantity (stress or strain) and its time rate as its argument. Such an equation leads to the usual linear damage accumulation law and is incapable of modelling sequence effects. A power function form is proposed and integrated for a trapezoidal waveform with unequal tension and compression holdtimes. Using total strains only this equation can model the separate influences of frequency, holdtime, unequal effects of tension and compression holdtime, as well as mean stress (strain) effects. It includes Coffin’s frequency approach as a special case. The equation is shown to correlate low-cycle fatigue data with holdtime of type 304 stainless steel at 1200°F (649°C) and of cast IN 738 at 1600°F (871°C). It is then used to predict the lifetime for other tests for which no experiments have yet been reported.

scholarly journals A Mechanism-Based Approach From Low Cycle Fatigue to Thermomechanical Fatigue Life Prediction

2015 ◽  
Vol 138 (7) ◽  
Author(s):  
Xijia Wu ◽  
Zhong Zhang
Keyword(s):  
Damage Accumulation ◽  
Low Cycle Fatigue ◽  
Strain Curve ◽  
Thermomechanical Fatigue ◽  
Cyclic Stress ◽  
Ductile Cast Iron ◽  
Cycle Fatigue ◽  
Physical Strain ◽  
Creep Fatigue ◽  
Damage Process

Deformation and damage accumulation occur by fundamental dislocation and diffusion mechanisms. An integrated creep–fatigue theory (ICFT) has been developed, based on the physical strain decomposition rule that recognizes the role of each deformation mechanism, and thus relate damage accumulation to its underlying physical mechanism(s). The ICFT formulates the overall damage accumulation as a holistic damage process consisting of nucleation and propagation of surface/subsurface cracks in coalescence with internally distributed damage/discontinuities. These guiding principles run through both isothermal low cycle fatigue (LCF) and thermomechanical fatigue (TMF) under general conditions. This paper presents a methodology using mechanism-based constitutive equations to describe the cyclic stress–strain curve and the nonlinear damage accumulation equation incorporating (i) rate-independent plasticity-induced fatigue, (ii) intergranular embrittlement (IE), (iii) creep, and (iv) oxidation to predict LCF and TMF lives of ductile cast iron (DCI). The complication of the mechanisms and their interactions in this material provide a good demonstration case for the model, which is in good agreement with the experimental observations.

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