In this paper a statistical model of grain size distribution is proposed. It is su¢ ciently simple to be studied analytically. The resulting grain size distribution does not contain …tting parameters and describes reasonably well the experimental data. The statistical model is based on the suggested in the paper tessellation condition, the necessary and su¢ cient condition for a set of grains t...

A significant contribution to the overall mechanical behaviour of microstructural materials is provided by the interaction of dislocation movement and grain boundaries. As a consequence, polycrystals are observed to respond with a higher strength for smaller grain sizes, a phenomenon which can not be modeled with classical single crystal plasticity theories. Gradient plasticity theories have be...

There has been considerable success over the past five decades in developing a phenomenological and micromechanism-based understanding of lastic flow, creep and superplasticity. Although it is widely known that grain sizes have a distribution in polycrystals and nanocrystals, this factor s usually not included in most analysis of deformation and failure. Experimental observations relating to th...

this paper presents a simple yet powerful original approach for approximating dispersivity in porous media. the key to this approach is both use of least-squares criterion and image processing technique. two dimensional transparent models, including horizontal and vertical configurations, under different combinations of grain sizes and pore velocities, experimented. concentration data were obta...

To investigate the effect of grain sizes on hydrogen embrittlement 4N-purity iron, miniature tensile tests were conducted after charging for ultrafine-grained specimens produced by high-pressure torsion and subsequent annealing. Hydrogen indexes defined from reduction area increased with decreasing size, shear-type fracture occurred fine dimples surface diagonally raptured specimen a smaller si...

The dependency of uniform corrosion of structural steel on the average grain size (D) should be quantified for design purposes. In the present work, a spectrum of grain sizes was obtained by simple heat treatment routes in st37 structural steel. It was revealed that the corrosion current density (icorr) increased by grain refinement, which was related to the increased density of grain boundarie...

ABSTRACT We study the linear growth and non-linear saturation of ‘acoustic Resonant Drag Instability’ (RDI) when dust grains, which drive instability, have a wide, continuous spectrum different sizes. This physics is generally applicable to dusty winds driven by radiation pressure, such as occurs around red-giant stars, star-forming regions, or active galactic nuclei. Depending on physical size...