The fatigue behavior of a nickel-base superalloy was investigated under total strain-controlled mode at high temperature. The fatigue life, cyclic stress response behavior and hysteresis loop of the superalloy were investigated under isothermal low cycle fatigue (LCF) conditions. The superalloy exhibited cyclic hardening and softening behaviors during the process of fatigue loading. The hystere...

A constitutive model based on two–dimensional unstructured Galerkin finite volume method (GFVM) is introduced and applied for analyzing nonlinear behavior of cracked concrete structures in equilibrium condition. The developed iterative solver treats concrete as an orthotropic nonlinear material and considers the softening and hardening behavior of concrete under compression and tension by using...

Dynamic pore collapse in porous materials is studied by analyzing the finite deformation of an elastic/viscoplastic spherical shell under impulsive pressure loading. Effects of dynamic loading rate, pore size, initial porosity, strain-rate sensitivity, strain hardening, thermal softening, and mass density of the matrix material on the pore collapse process are examined and results are compared ...

in the first impounding of rockfill dams, additional settlements occur in upstream side in saturated rockfills due to collapse phenomenon even high rainy seasons can cause additional deformation in the dumped rockfills. unfortunately these displacements are not taken into account in the conventional numerical models which are currently used to predict embankment dam behavior during impounding. ...

The detailed contribution of microstructural-level phenomena, such as dislocation structure development and annihilation, well inter-granular intra-granular backstress fields, to reverse loading behavior in metal alloys remains an area active research debate. ability predict unloading nonlinearities, the Bauschinger effect (BE), changes hardening rates during is necessary for accurate modeling ...

Abstract Inconel 625 nickel alloy with its attractive high-temperature strength, excellent corrosion and oxidation resistance is mainly used for critical applications in demanding environments, both as-cast wrought conditions. Hot processing of this crucial achieving tailored mechanical properties due to the significant variation microstructural changes varying process parameters like temperatu...

Based on the dominated deformation mechanisms of superplastic materials, an assumption for micro-damage evolution is presented. Then, a set of uni®ed viscoplastic-damage constitutive equations is proposed to model material hardening due to the increase of dislocation density and grain growth, as well as material softening due to intergranular void nucleation and growth. The effects of the harde...

The mechanical properties of materials are highly sensitive to the content impurities and point defects due their interaction with plastic deformation carriers-dislocations. This opens up possibility some extent control through alloying creating solid solutions. In a number crystalline materials, in addition well-known solid-solution strengthening region low concentration solution atoms, opposi...

Metallic nanowires usually exhibit ultrahigh strength but low tensile ductility owing to their limited strain hardening capability. Here we study the unique strain hardening behavior of the five-fold twinned Ag nanowires by nanomechanical testing and atomistic modeling. In situ tensile tests within a scanning electron microscope revealed strong strain hardening behavior of the five-fold twinned...