Questions tagged [stress-strain]
Questions related to the physical quantities of stress and strain in materials systems.
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Print full stress tensor in ASE to calculate Green Kubo viscosity
I would like to print out the off diagonal components of the full stress tensor in ASE. The goal is then to calculate the Green Kubo viscosity. One should use the ensemble average of the off diagonal ...
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Structural phase transition under uniaxial strain
I am trying calculate a strain-induced phase transition in some weakly correlated crystalline material using Quantum Espresso (QE). The compound has two (experimentally observed) phases, one of which ...
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ASE/XTB: zero temperature and stress in MD simulation
I want to see how the volume and pressure of my cell is changing during a MD relaxation in ASE. I used the atom.get_volume() and ...
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Why is strain rate used instead of absolute strain for modelling stress relaxation of a viscoelastic material using the Maxwell model?
I don't quite fully understand the derivation of the Maxwell model for prediction of stress relaxation for viscoelstic materials. usually the governing equation can be described in terms of strain ...
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How to calculate 2D elastic constants of boron nitride monolayers from uniaxial strains?
I am trying to calculate 2D elastic constants of a hexagonal boron nitride (hBN) monolayer.
The unit cell is the primitive cell and the Cartesian coordinate is set as follows.
The elastic constants $...
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Reference textbooks for calculating pressures/stress/strain/tensors?
Is there a good reference textbook for calculating pressures/stress/strain/tensors in materials - vapor, liquids and solids? Pure physics is fine, but it would be a bonus if it also included force-...
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How to bond two laminates (same material) separated by distance using compressive pressure in LAMMPS?
I would like to simulate the bonding process using compressive pressure for two layers of the same material. Applying a uniaxial strain and using the deform tag in LAMMPS requires PBC in all ...
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Calculating strain field. Need idea on how to do that [closed]
Recently I am learning VASP. I am trying to see different properties of two-level system (TLS). For example, checking amorphous silicon as a test case (along with it's vacancy structures as well). ...
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Is it possible to define a property like strain to characterize the structural change?
Lets suppose that I have an atom chain like system 1 below. Now, some interaction made one atom to move out of the chain, like shown in system 2 (the moved atom remains bounded but in another position)...
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How to perform Strain induced properties in Quantum ESPRESSO?
I have to perform strain engineering in a material. The strain would be expansive strain and compressive strain. How do I perform those both?
I am currently using the ...
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How to distinguish between deformation mechanisms in creep experiment? [closed]
As I'm learning more about viscoelasticity and creep experiments, I'm trying to understand how to distinguish between the different deformation mechanisms.
In general, when a sample of viscoelastic ...
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Define stress-strain for a multi-wall carbon nanotubes bundle [closed]
I want to simulate a MWCNT bundle in which the central MWCNT is pulled out of the bundle.
How to define the stress/strain curve of such system?
I am building my system with scikit-nano and using ...
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How to find the Cauchy stress tensor in solids using ab-initio methods?
I want to find the Cauchy stress tensor in certain materials with ab initio methods. I already have the analytical form of my own definition of "energy" and "forces" (not from DFT),...
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Mathematical models for the plastic region in the tensile test
The tensile test of a material consists of subjecting a standardized specimen to an increasing axial tensile stress until it breaks. During its performance in the laboratory, we can plot a stress-...
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A viscoelastic material with nonconvex memory kernel?
The title is basically my question. Viscoelastic materials are characterized by a constitutive equation between stress and strain involving a convolution integral. This integral is weighted with a ...
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How to find Young's Modulus using stress strain curve using Python?
I am trying to find the
The Young's Modulus of an aluminum alloy
The yield stress
Below is the data for the stress-strain curve. I tried finding the region where the slope is constant and to my ...
user1015
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How does a complete basis set remove Pulay forces/stress?
When finding nuclear forces for the true electronic wavefunction, thanks to the Hellmann-Feynman theorem we only need to consider explicit derivatives with respect to the nuclear coordinates $\mathbf{...
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