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Processing of Ultrafine-grained Cu-Fe-Cr Composite by Equal Channel Angular Pressing K.
All Cu-Fe-Cr specimens showed ultrafine-grained microstructures with the shape and distribution of Fe-Cr phase dependent on the processing routes.
Iwahashi et al. [17] studied the effect of processing parameters on the grain refinement in Al and found that the subgrain and grain size are in the range of 0.5-1.5 µm.
The size of second phase particles decreased with increasing number of passes.
Fig. 8 shows the variation of the hardness against the number of passes.

A small number of crystal plasticity simulations and tensile tests are carried out with the aim of demonstrating that control of twinning can improve the uniform elongation of magnesium based alloys.
A number of authors have recently drawn attention to this fact in their analysis of Mg-3Al-1Zn subjected to Equal Channel Angular Pressing [2,3].
Fraction of Grains Undergoing Twinning - Sachs Analysis The fraction of grains undergoing twinning, XT, is determined, in part, by the texture.
Assuming that only one deformation mode is active in each grain, the grains expected to twin can be estimated by combining a Schmid factor (SF) analysis with the fact that twinning only works in one direction.
That is, more grains should undergo twinning under uniaxial compression, compared with tension, for a random aggregate.

The obtained results can be used to model grain growth in molecular dynamics studies.
Among others, two such mechanisms that involve grain boundaries are Strain hardening and Grain size hardening.
However, the number of computational studies for low-Miller-index, i.e., (111), (100) and (110) interfaces/grain boundaries is rather scarce.
Thomson et al. [5] investigated the interactions of gallium atoms in Σ=11 (113) grain boundary.
Also, for each entry the number of atoms and space group is given.

Equal channel angular pressing (ECAP) is useful method to obtain the ultra-fine grained and the high hardened metal.
The as-deformed metals retained high dislocation densities, a large number of low angle sub-grain boundaries, and showed being in non-equilibrium configurations [7].
The grain of as-heat treated Al exhibited an equi-axial, uniform, and coarse structure.
The grains were elongated, having an angle of 15 - 30 degrees to the ECAPed out direction.
Rotated Goss component, {110}<110>, increases with the number of passes ECAP, decreases with annealing.

To illustrate the effects, the average grain stack model was introduced.
The breakdown electrical field EB of the varistors is determined by barrier density n per unit length and barrier voltage Vb [11]: EB=n ·Vb (1) where n also presents the average grain number per unit length.
The resistivities and capacitances of grains are much lower than those of grain boundary layers.
The capacitance Cgb of single grain boundary Cgb=εBε0 d 2/t (4) where εB is the relative permittivity of the grain boundary material, ε 0 is vacuum permittivity. d and t are mean grain size and grain boundary thickness, respectively.
The thickness of grain boundary dielectric layer is normally in the range of 10~100nm, while the grain size d is in the magnitude order of µm.

In this paper, we accordingly analyze the REV for different porous media with different grain sizes based on computed tomography (CT) measurement.
Our results show that that CT measurement is a relible method for REV analysis and that there is an appropriate linear relationship between grain size and REV.
REV of glass-bead packs with different grain sizes The grain sizes of glass beads are shown in Table 1.
(2) There is an appropriate linear relationship between the grain size and REV.
Glover and Nicholas Déry :Streaming potential coupling coefficient of quartz glass bead packs:Dependence on grain diameter, pore size, and pore throat radius.

From matellographic analysis, grain refinement was observed obviously beneath the dimple.
Ji et al. [11] built micro-scale numerical simulation model of LPF based on material grain.
The morphology of the grains under the laser power density of 5.07GW/cm2 and the repeated shock number of 4 is shown in Fig. 8.
The average size of the refined grain is 6.26μm.
Compared with the grain size of 11.36μm which is far away from the dimple, the grains in the refined layer are refined by 44.89%.

Besides, the average grain size of alumina ceramic is about 2.8μm, and the effect of inhibition on grain growth of alumina ceramics was obvious.
Therefore, the grain boundary migration speed was reduced, and the growth of the grain boundary was prevented.
The grain size of the samples was about 2.8μm and the grain size distribution was uniform (refer with: Fig.7 (c)).
When the speed of grain boundary migration was greater than that of the pores, the pores were wrapped in the grain.
Hot-Pressed Sintering of Fine Grained Alumina Ceramics [J].

Introduction Nanocrystalline materials consisting of nanometer-sized crystallites contain a large number of interfaces such as grain boundaries and triple junctions, and thus, a large volume fraction of atoms are associated with the intercrystalline region [1].
The average grain size increases drastically above 400°C.
The blue colored area indicates the <111>//ND grains and the red one does the <100>//ND grains.
Furthermore, the growth of the <111>//ND grains may be referred to as 'abnormal grain growth' in length scale, i.e.
Abnormal grain growth tends to occur when normal grain growth is suppressed by precipitate particles [7] and/or by solute atoms [8].

SEM/EBSD local orientation measurements on partly recrystallized samples demonstrate the appearance of a specific number of new orientation groups of recrystallized grains, which resulted from rotation of the deformed crystal orientations around axes lying near (but rarely at) selected the <111> directions.
Despite the scatter of the recrystallized grain orientations, it can be claimed with certainty that only a finite number of their groups were observed.
‘Incoherent’ twin boundaries between growing grains.
They appeared between the growing grains.
Therefore, for lightly annealed samples the number of recrystallized grains significantly decreases as the middle sample section approaches; this may reduce the ‘quality’ of performed analysis.