X-ray diffraction, optical microscopy and microhardness testing have been used to study properties which develop in micro-cut AISI 1045 steel. The influence of the ploughing effect on residual stresses, surface deformation and work hardening, and the tool quality were investigated. Tensile residual stresses, caused by the heat generated in the material during the cutting process, were observed ...

Analysis of reciprocating equipment piston rod leads to nonlinear elastic-plastic deformation analysis of rod with initial imperfection under axial dynamic load. In this paper a new and effective model and analytical formulations are presented to evaluate dynamic deformation and elastic-plastic stresses of reciprocating machine piston rod. This new method has capability to account for geometric...

Additives were tested for their ability to modify the rheology of lignocellulosic biomass. Additive types included water-soluble polymers (WSPs), surfactants, and fine particles. WSPs were the most effective rheological modifiers, reducing yield stresses of concentrated biomass by 60–80% for additive concentrations of 1–2 wt. % (based on mass of dry biomass solids). Yield stress and plastic vis...

We report experimental characterization of shear transformation zones (STZs) for plastic flow of bulk metallic glasses (BMGs) based on a newly developed cooperative shearing model [Johnson WL, Samwer K (2005) A universal criterion for plastic yielding of metallic glasses with a (T/T(g))(2/3) temperature dependence. Phys Rev Lett 95: 195501]. The good agreement between experimental measurements ...

The different shot peening responds of a grey cast iron (GI) with its flake graphite and a compacted cast iron (CGI) with its vermicular graphite was analyzed and compared in this paper. For peening using identical parameters, CGI showed a larger plastic deformation zone with higher subsurface compressive stresses than GI. Electron backscatter diffraction (EBSD) mapping and backscatter electron...

A new formulation of the self consistent model has been applied to predict the plastic behaviour of A1-Li Alloys. This model enables to take into account simultaneously the crystallographic texture, the morphology of grains, the internal stresses evolution and the anisotropy of intracrystalline hardening. Microscopic observations and analyses of crystallographic textures are used t o constitute...

A new approach to the description of processes of plastic defonnation is developed. Within this approach, the evolution of a dislocation ensemble is detennined by both dislocation multiplication and dislocation transfonnations with both the processes occurring against the background of elastic stresses produced by the dislocation ensemble itself. Apart from the equations of detailed balance tha...

Crystalline solids undergo plastic deformation and subsequently flow when subjected to stresses beyond their elastic limit. In nature most crystalline solids exist in polycrystalline form. Simulating plastic flows in polycrystalline solids has wide ranging applications, from material processing to understanding intermittency of earthquake dynamics. Using phase field crystal (PFC) model we show ...

We present an experimental investigation of the effects of surface passivation, film thickness and grain size on the plastic behavior of freestanding Cu thin films. The stress–strain curves of the films are measured using the plane–strain bulge test. Films with a passivation layer on one or both surfaces have an offset yield stress that increases significantly with decreasing film thickness; th...

We consider rate-independent models of static and quasistatic plasticity with hardening. These models are usually stated in terms of variational inequalities of the first or second kind, for the primal and dual formulations, respectively. In the static case, the dual variational inequality can be interpreted as the necessary and sufficient optimality conditions for an underlying optimization pr...