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Showing 1 to 10 of 10 for “"Strain gradient plasticity"”.
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Numerical investigation of theories of strain-gradient plasticity
In this work, a higher-order irrotational strain gradient plasticity theory is studied in the small strain regime. This theory is based on that originally developed by Gurtin and Anand, and includes both dissipative and energetic contributions. A detailed numerical study is based on the problem of …
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Strain gradient plasticity-based modeling of damage and fracture
… At the continuum level, phenomenological strain gradient plasticity (SGP) formulations have been developed to extend plasticity theory to small scales. Grounded on the physical notion of geometrically necessary dislocations (GNDs, associated with non-uniform plastic deformation), SGP …
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A Conventional Theory of Mechanism-Based Strain Gradient Plasticity
CMSG is also used to study the indentation size effect (ISE) observed in micro and nanoindentation experiments. Different hardness trends with different indenter shapes obtained from CMSG agree very well with the experimental measurement.
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Continuum and crystal strain gradient plasticity with energetic and dissipative length scales
… Numerical methods. Since conventional continuum plasticity and heat transfer theories, based on the local thermodynamic equilibrium, do not account for the microstructural characteristics of materials, they cannot be used to adequately address the observed mechanical and thermal response of the …
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On a class of strain gradient plasticity theories : formulation and numerical implementation
This study develops strain-gradient theories for isotropic and crystal plasticity. The following four theories were developed and numerically implemented: * A one-dimensional theory to understand the basic nature of strain gradient theories; * A small deformation crystal plasticity theory; * A …
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Variational constitutive updates for strain gradient isotropic plasticity
In the past decades, various strain gradient isotropic plasticity theories have been developed to describe the size-dependence plastic deformation mechanisms observed experimentally in micron-indentation, torsion, bending and thin-film bulge tests in metallic materials. Strain gradient plasticity …
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Length-Scale Effects on Nano-Scale Materials Behavior
… the first time, we observe absence of permanent strain hardening in aluminum for grain sizes below 50 nm. We propose that this is due to the absence of dislocations at interior of grains at this length-scale. (5) For the first time, we observe grain size dependence of the strain gradient …
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Computational modeling of size-dependent superelasticity in shape memory alloys
… characterized by the development of significant strains which are fully recoverable upon unloading, and also characterized by the stress-hysteresis in the loading and unloading cycle which corresponds to the energy dissipated during phase transformations. Recently, experiments have revealed …
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Multiscale Experimental Analysis in Plasticity: Linking Dislocation Structures to Continuum Fields
… phenomenon, and has been incorporated to crystal plasticity theories to analyze the size effect in metals for almost a decade ago. Although the theories suffice to predict the size effect in metals, they are largely phenomenological. Here a novel experimental method is developed to resolve the …
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Computational and theoretical problems in fractional and higher-order theories for modeling biomechanical media
L'abstract è presente nell'allegato / the abstract is in the attachment