The plastic behaviour of ?100? and ?111? textured polycrystalline metals during simultaneous torsion and extension

The avian eggshell is one of the most rapidly mineralizing biological systems known. In situ, 5g of calcium carbonate are crystallized in less than 20 hrs to fabricate the shell. Although there have been much work about the formation of eggshells, controversy about the nucleation and growth mechanisms of the calcite crystals, and their texture in the eggshell, still remain unclear. In this report the microstructure and microchemistry of avian eggshells have been analyzed using transmission electron microscope (TEM) and energy dispersive spectroscopy (EDS).Fresh white and dry brown eggshells were broken and fixed in Karnosky's fixative (kaltitanden) for 2 hrs, then rinsed in distilled H2O. Small speckles of the eggshells were embedded in Spurr medium and thin sections were made ultramicrotome.The crystalline part of eggshells are composed of many small plate-like calcite grains, whose plate normals are approximately parallel to the shell surface. The sizes of the grains are about 0.3×0.3×1 μm3 (Fig.l). These grains are not as closely packed as man-made polycrystalline metals and ceramics, and small gaps between adjacent grains are visible indicating the absence of conventional grain boundaries.

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The physics of plastic behaviour of crystalline and amorphous solids

Annales de Physique ◽

10.1051/anphys/197803030207 ◽

1978 ◽

Vol 3 ◽

pp. 207-220 ◽

Cited By ~ 18

Author(s):

B. Escaig

Keyword(s):

Amorphous Solids ◽

Plastic Behaviour

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Constitutive modelling of the thermo-plastic behaviour of soils

Revue européenne de génie civil ◽

10.3166/regc.9.635-650 ◽

2005 ◽

Vol 9 (5-6) ◽

pp. 635-650 ◽

Cited By ~ 2

Author(s):

Lyesse Laloui ◽

Cane Cekerevac ◽

Bertrand François

Keyword(s):

Constitutive Modelling ◽

Plastic Behaviour

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PRISMS-Fatigue computational framework for fatigue analysis in polycrystalline metals and alloys

npj Computational Materials ◽

10.1038/s41524-021-00506-8 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Mohammadreza Yaghoobi ◽

Krzysztof S. Stopka ◽

Aaditya Lakshmanan ◽

Veera Sundararaghavan ◽

John E. Allison ◽

...

Keyword(s):

Open Source ◽

Open Source Software ◽

Large Scale ◽

Metals And Alloys ◽

Analysis Tool ◽

Computational Framework ◽

Crystal Plasticity Finite Element ◽

Polycrystalline Metals ◽

Simulation Based ◽

Open Source Framework

AbstractThe PRISMS-Fatigue open-source framework for simulation-based analysis of microstructural influences on fatigue resistance for polycrystalline metals and alloys is presented here. The framework uses the crystal plasticity finite element method as its microstructure analysis tool and provides a highly efficient, scalable, flexible, and easy-to-use ICME community platform. The PRISMS-Fatigue framework is linked to different open-source software to instantiate microstructures, compute the material response, and assess fatigue indicator parameters. The performance of PRISMS-Fatigue is benchmarked against a similar framework implemented using ABAQUS. Results indicate that the multilevel parallelism scheme of PRISMS-Fatigue is more efficient and scalable than ABAQUS for large-scale fatigue simulations. The performance and flexibility of this framework is demonstrated with various examples that assess the driving force for fatigue crack formation of microstructures with different crystallographic textures, grain morphologies, and grain numbers, and under different multiaxial strain states, strain magnitudes, and boundary conditions.

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