A Micromechanical Approach to Low Cycle Fatigue Analysis and Life Prediction of Heterogeneous Materials

A weight function method based on strain parameters is proposed to determine the critical plane in low-cycle fatigue region under both constant and variable amplitude tension–torsion loadings. The critical plane is defined by the weighted mean maximum absolute shear strain plane. Combined with the critical plane determined by the proposed method, strain-based fatigue life prediction models and Wang-Brown’s multiaxial cycle counting method are employed to predict the fatigue life. The experimental critical plane orientation and fatigue life data under constant and variable amplitude tension–torsion loadings are used to verify the proposed method. The results show that the proposed method is appropriate to determine the critical plane under both constant and variable amplitude loadings.

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LOW CYCLE FATIGUE BEHAVIOR AND LIFE PREDICTION OF A CAST COBALT-BASED SUPERALLOY

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194512003261 ◽

2012 ◽

Vol 06 ◽

pp. 251-256

Author(s):

HO-YOUNG YANG ◽

JAE-HOON KIM ◽

KEUN-BONG YOO

Keyword(s):

Fatigue Life ◽

Strain Energy ◽

Life Prediction ◽

Prediction Models ◽

Low Cycle Fatigue ◽

Fatigue Behavior ◽

Total Strain ◽

Cycle Fatigue ◽

Total Strain Range ◽

Different Temperatures

Co -base superalloys have been applied in the stationary components of gas turbine owing to their excellent high temperature properties. Low cycle fatigue data on ECY-768 reported in a companion paper were used to evaluate fatigue life prediction models. In this study, low cycle fatigue tests are performed as the variables of total strain range and temperatures. The relations between plastic and total strain energy densities and number of cycles to failure are examined in order to predict the low cycle fatigue life of Cobalt-based super alloy at different temperatures. The fatigue lives is evaluated using predicted by Coffin-Manson method and strain energy methods is compared with the measured fatigue lives at different temperatures. The microstructure observing was performed for how affect able to low-cycle fatigue life by increasing the temperature.

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A Multiaxial Low Cycle Fatigue Life Prediction Model for Both Proportional and Non-proportional Loading Conditions

Journal of Materials Engineering and Performance ◽

10.1007/s11665-014-1107-4 ◽

2014 ◽

Vol 23 (9) ◽

pp. 3100-3107 ◽

Cited By ~ 4

Author(s):

Surajit Kumar Paul

Keyword(s):

Fatigue Life ◽

Prediction Model ◽

Life Prediction ◽

Low Cycle Fatigue ◽

Fatigue Life Prediction ◽

Loading Conditions ◽

Cycle Fatigue ◽

Proportional Loading ◽

Life Prediction Model

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Anisotropic Life Prediction for Single Crystal Nickel-Base Flat Plate with a Hole

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.891-892.1033 ◽

2014 ◽

Vol 891-892 ◽

pp. 1033-1038

Author(s):

Cheng Li Dong ◽

Hui Chen Yu ◽

Ying Li

Keyword(s):

Single Crystal ◽

Flat Plate ◽

Life Prediction ◽

Failure Strain ◽

Low Cycle Fatigue ◽

Cycle Fatigue ◽

The Finite Element Method ◽

Nickel Base Superalloys ◽

Nickel Base ◽

Elastoplastic Constitutive Model

The material properties of single crystal (SC) superalloys are orientation-dependent. To fully exploit the material capacity, the life modeling needs to consider the anisotropy. In the present study the life modeling of SC nickel-base superalloys is considered by employing the modified Mücker's anisotropic theory in which a Hill type function is utilized for describing the anisotropic failure. Strain-controlled low cycle fatigue (LCF) experiments of SC nickel-base superalloys at different crystallographic orientations (i.e.[00, [01 and [11) under high temperatures (i.e.760°C) are carried out to verify the modeling availability for the modified Mücker's anisotropic theory. Further, based on the stress-strain field obtained by the anisotropic elastoplastic constitutive model coupled with the finite element method (FEM), the modified Mücker's anisotropic theory is employed to predict the fatigue life for SC flat plate with a hole.

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