the purpose of this study is to survey cross section changes of the animal brain samples during the tension and compression tests and comparison of the experimental results for three animals: bovine, sheep, and rabbit. a linear elastic theory with considering the necking in tension and barreling in compression has been considered for brain tissue. bridgman method for tension and cross section u...

Abstract Necking is a very common phenomenon in uniaxial tensile experiments. It particularly prominent materials with high-stress levels. can be considered deformation destabilization or localized concentration of deformation. The occurrence this lead to the failure stress-strain curve material. Therefore, paper will examine problem correction tension for high levels yield stress. Due class ma...

The dynamic necking instability of a rod of a non-linear viscoplastic material as formed in shaped charges is investigated. A two-dimensional linear Lagrangian perturbation method leads to a single fourth order partial differential equation with time-dependent coefficients. The growth of disturbancies depends of the interplay between the stabilizing inertial and viscous effects, and the destabi...

The purpose of this study is to survey cross section changes of the animal brain samples during the tension and compression tests and comparison of the experimental results for three animals: bovine, sheep, and rabbit. A linear elastic theory with considering the necking in tension and barreling in compression has been considered for brain tissue. Bridgman method for tension and cross section u...

Abstract Nanograin materials have superior properties in mechanics, physics and chemistry. Here, we found a new phenomenon that nanograin formation spontaneously occurs the process of ductile fracture for titanium alloy, dominating mechanism is local severe-plastic-deformation (LSPD). The microstructure evolution during entire monotonic tension was revealed to further understand from plastic de...

We present atomistic simulations of h110i oriented gold nanowires under tensile deformation. We find that h110i gold nanowires tend to form elongated, stable nanobridges upon necking, which is in agreement with previous experimental observations. In addition, the simulations reveal that the formation of a high strength multishell lattice structure during the plastic deformation of the h110i wir...

In this paper, four plastic instability criteria, which are based on the bifurcation theory, coupled with GTN damage model for prediction of diffuse and localized necking. General (GB) criterion limit-point (LPB) used to predict necking, while loss ellipticity (LOE) strong (LOSE) The resulting constitutive equations criteria implemented into finite element code ABAQUS/Standard. formulated withi...