The Jacobian of deformation at a material point can be decomposed into the stretch tensor and the rotation tensor. Thus, varying Jacobians of deformation at the neighboring material points in the deforming volume of solid continua would yield varying stretch and rotation tensors at the material points. Measures of strain, such as Green’s strain, at a material point are purely a function of the ...

Surface discharge is one of the reasons for insulation failure. Polyimide (PI) used in gas-solid high-frequency electric power equipment. Therefore, based on density functional theory, effects single molecular chain structure, energy level, states, electrostatic potential, excited state and other micro parameters under external field trap formation surface both PI polar- group- OH<sup>– &...

The suspended electrothermal polysilicon micro beams generate displacements and forces by thermal buckling effects. In the previous electro-thermal and thermo-elastic models of suspended polysilicon micro beams, the thermo-mechanical properties of polysilicon have been considered constant over a wide rang of temperature (20900°C). In reality, the thermo-mechanical properties of polysilicon depe...

Current imaging technique such as micro X-ray CT can provide us detailed 3D micro-structures of porous rocks that can be used in numerical simulation so as to predict elastic properties of rocks saturated with different fluids. However, limited by the resolution the imaging process can provide, we usually lose the small features of rocks such as cracks and micro-pores, consequences of which can...

In culture migrating and interacting amoeboid cells can form nematic liquid crystal phases. A polar nematic liquid crystal is formed if the interaction has a polar symmetry. One type of white blood cells (granulocytes) form clusters where the cells are oriented towards the center. The core of such an orientational defect (disclination) is either a granulocyte forced to be in an isotropic state ...

In this work, the mechanism for fracture of brittle substances such as rocks under a uniform normal tension is considered. The oriented straight micro-cracks are mostly created in all the polycrystalline materials resulting from the stress concentrations. The present work focuses on the interactions of the pre-existing micro-cracks, which can grow and propagate within a rock-like specimen. The ...

In this study, two-dimensional finite element modeling was used to study the simultaneous effect of the cell shape and regular cell distribution on the anisotropy of the elastic properties of 316L stainless steel foam. In this way, the uniaxial compressive stress-strain curve was predicted using a geometric model and fully solid 316L stainless steel. The results showed that the elastic tangent ...

Large scale molecular dynamics simulations of iron at high pressure and temperature are performed to investigate the physics of shear softening. A solid 16×10(6) atoms sample of iron is grown out of the liquid with a small solid immersed in it at the start of simulation. We observe that diffusion in the sheared solid is similar to that in liquid, even though at different time scales. This allow...

Keywords: Phase transformation Phase-field Interfacial phases Internal stresses Intermediate melt Nucleation a b s t r a c t A thermodynamically consistent phase-field (PF) theory for phase transformations (PTs) between three different phases is developed with emphases on the effect of a stress tensor and interface interactions. The phase equilibrium and stability conditions for homogeneous pha...