A Two Surface Plasticity Model With Bounding Surface Softening

Two surface plasticity models have been used increasingly in recent years to model not only uniaxial, cyclic plasticity but also multiaxial and nonproportional histories. A two surface model is presented here which predicts the increased hardening due to out-of-phase cycling in a natural way. It includes a mechanism by which the bounding surface contracts when the yield surface is not in contact. This provides a mechanism that is useful for modeling cycling behavior. Predictions of the model with experiments at moderate strain are presented.

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Mechanical Fatigue Simulation by Unconventional Plasticity Model

Volume 3: Safety and Reliability; Materials Technology; Douglas Faulkner Symposium on Reliability and Ultimate Strength of Marine Structures ◽

10.1115/omae2006-92017 ◽

2006 ◽

Author(s):

Seiichiro Tsutsumi ◽

Masahiro Toyosada ◽

Daiki Yajima ◽

Koji Gotoh ◽

Koichi Hashiguchi

Keyword(s):

Yield Surface ◽

Deformation Behavior ◽

Fem Analysis ◽

Cyclic Plasticity ◽

Surface Model ◽

Plasticity Model ◽

Cyclic Loading Condition ◽

Mechanical Fatigue ◽

Deformation Behaviors ◽

Cyclic Plasticity Model

The deformation behavior of a structure under cyclic loading condition is simulated by using FEM analysis in which a cyclic plasticity model, so-called extended subloading surface model, is incorporated. The adopted cyclic plasticity model is categorized in the framework of the unconventional plasticity model premising that the interior of the yield surface is not a purely elastic domain. The developed FEM program does not include algorithms for both the yielding-judgment and the control of stress so as to lie on the yield surface, since the subloading surface model has the stress controlling function so that a stress approaches the yield surface automatically. In this study, several examples of FEM analysis on the cyclic deformation behaviors are presented to show the potential of the developed FEM program and an incorporated cyclic plasticity model.

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Fully implicit numerical integration of the Yoshida-Uemori two-surface plasticity model with isotropic hardening stagnation

Frattura ed Integrità Strutturale ◽

10.3221/igf-esis.57.10 ◽

2021 ◽

Vol 15 (57) ◽

pp. 114-126

Author(s):

Riccardo Fincato ◽

Seiichiro Tsutsumi ◽

Alex Zilio ◽

Gianluca Mazzucco ◽

Valentina Salomoni

Keyword(s):

Large Strain ◽

Cyclic Plasticity ◽

Integration Scheme ◽

Small Scale ◽

Isotropic Hardening ◽

Surface Model ◽

Plasticity Model ◽

Surface Plasticity ◽

Fully Implicit ◽

Novel Strategy

The paper deals with the numerical investigation and implementation of the two-surface plasticity model (or bounding surface model). This plasticity theory allows to describe the deformation behavior under large strain cyclic plasticity and the material stress-strain responses at small-scale re-yielding after large pre-straining. A novel strategy to model the isotropic hardening stagnation is developed within a fully implicit integration scheme in order to speed up the computation and to improve the material description.

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