A Combined Finite Element and Self-Consistent Model; Validation by Neutron Diffraction Strain Scanning

Time of flight neutron diffraction method was applied to measure elastic lattice strains in austenitic steel during "in situ" tensile test. Comparing experimental data with self-consistent model, the critical resolved shear stress and hardening parameters were determined for polycrystalline grains. The result allowed us to determine the main component of the stress localization tensor, relating the rate of grain stress with the applied macrostress rate. The evolution of concentration tensor in function of the applied macrostress was analyzed. Finally, the load transfer between grains during yielding of the sample was studied.

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Comparison of finite-element and homogenization methods for modelling the viscoplastic behaviour of a S2–columnar-ice polycrystal

Annals of Glaciology ◽

10.3189/172756400781820598 ◽

2000 ◽

Vol 30 ◽

pp. 115-120 ◽

Cited By ~ 10

Author(s):

Jacques Meyssonnier ◽

Armelle Philip

Keyword(s):

Finite Element ◽

Strain Rate ◽

Transversely Isotropic ◽

Uniform Strain ◽

Upper And Lower Bounds ◽

Uniform Stress ◽

Consistent Model ◽

Self Consistent ◽

Polycrystalline Ice ◽

Homogenization Methods

AbstractThe main homogenization schemes used to model the behaviour of polycrystalline ice are assessed by studying the particular case of a two-dimensional polycrystal which represents natural S2–columnar ice. The results of the uniform-stress, uniform-strain-rate and one-site self-consistent models are compared to finite-element computations. The comparisons were made using the same model of grain, described as a continuous transversely isotropic medium, in the linear and non-linear cases. The uniform-stress and uniform-strain-rate models provide upper and lower bounds for the macroscopic fluidity which are too far from each other to be useful when a degree of anisotropy relevant to ice is considered. Although the self-consistent model gives a weak representation of the interaction between a grain and its surroundings, due to the strong anisotropy of the ice crystal, the resulting macroscopic behaviour is found to be acceptable when compared to the results from finite-element computations.

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Microstresses Determined by Neutron Diffraction and Self-consistent Model

Recent Advances in Experimental Mechanics ◽

10.1007/0-306-48410-2_45 ◽

2006 ◽

pp. 477-486

Author(s):

A. Baczmanski ◽

C. Braham ◽

R. Levy-Tubiana ◽

A. Lodini ◽

K. Wierzbanowski

Keyword(s):

Neutron Diffraction ◽

Consistent Model ◽

Self Consistent

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Accounting for a Distribution of Morphologies and Orientations on Stresses Analysis by X-Ray and Neutron Diffraction: Normalized Self-Consistent Modeling

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.996.82 ◽

2014 ◽

Vol 996 ◽

pp. 82-87

Author(s):

Viwanou Hounkpati ◽

Sylvain Fréour ◽

David Gloaguen ◽

Vincent Legrand

Keyword(s):

Neutron Diffraction ◽

Crystallographic Texture ◽

X Ray ◽

Consistent Model ◽

Self Consistent

The historical Eshelby-Kröner self-consistent model is only valid in the case when grains can be assumed similar to ellipsoids aligned preferentially along a same direction into the polycrystal. In this work, distributions of crystallites morphologies and geometrical orientations were accounted for, owing to the so-called generalized self-consistent model, in order to satisfy Hills averages principles. Different nonlinear εφψ-vs.-sin2ψ distributions were predicted in elasticity, even in the absence of crystallographic texture, in the case when several morphologies and geometrical orientations coexist within the same polycrystal.

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Study of Stresses in Texture Components Using Neutron Diffraction

Materials Science Forum ◽

10.4028/www.scientific.net/msf.768-769.289 ◽

2013 ◽

Vol 768-769 ◽

pp. 289-295

Author(s):

Andrzej Baczmański ◽

Elżbieta Gadalińska ◽

Sebastian Wroński ◽

Léa Le Joncour ◽

Benoit Panicaud ◽

...

Keyword(s):

Experimental Data ◽

Neutron Diffraction ◽

Tensile Load ◽

Group Method ◽

Model Calculations ◽

Lattice Strains ◽

Consistent Model ◽

Self Consistent ◽

Full Stress Tensor

In this work a new method for analysis of neutron diffraction results obtained during “in situ” tensile load is proposed and tested. The methodology is based on the measurements of lattice strains during “in situ” tensile test for several hkl reflections and for different orientations of the sample with respect to the scattering vector. As the result the full stress tensor for preferred texture orientations in function of applied stress can be determined with help of crystallite group method. The experimental data are presented and compared with self-consistent model calculations performed for groups of grains corresponding to the measured hkl reflections.

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Quantitative Estimation of the Second Order Plastic Incompatibility Stresses in Textured Duplex Steel

Materials Science Forum ◽

10.4028/www.scientific.net/msf.524-525.841 ◽

2006 ◽

Vol 524-525 ◽

pp. 841-846 ◽

Cited By ~ 1

Author(s):

Sebastian Wroński ◽

Andrzej Baczmanski ◽

Krzysztof Wierzbanowski ◽

Chedly Braham ◽

Rim Dakhlaoui ◽

...

Keyword(s):

Neutron Diffraction ◽

Elastoplastic Deformation ◽

Quantitative Estimation ◽

Diffraction Method ◽

Second Order ◽

The Self ◽

Two Phase ◽

Duplex Steel ◽

Consistent Model ◽

Self Consistent

A new method for determining the parameters characterising elastoplastic deformation of two-phase material is proposed. The method is based on the results of neutron diffraction, which are analysed using the self-consistent rate-independent model of elastoplastic deformation. The neutron diffraction method (time-of-flight technique) was applied and the self-consistent model was used to predict the second order stresses in austeno-ferritic duplex steel. Calculations based on the model were successfully compared with experimental results for both phases of the duplex steel.

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