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It can be clearly observed from the figure that the grain shape of the as-received material is elongated and flattened in a certain direction, and the grain may have a preferential orientation distribution, that is, the existence of the deformation texture.
The starting grain structures of 2219-T3 aluminum alloy.
Therefore, it is reasonable to believe that the anisotropy of compression creep strains should be due to the texture will cause different numbers of equivalent sliding system number (ESSN) in all directions [9], the larger the ESSN, the more the number of sliding systems that can be started simultaneously, the greater the number of dislocations that move, and the larger the creep strains.
Under the applied stress, grains with a large SF are liable to deform, while grains with a small SF are difficult to deform, resulting in anisotropic yield strength.
Effects of grain shape and texture on the yield strength anisotropy of Al-Li alloy sheet[J].

It was characterised by equiaxed γ grains of about 20µm, containing annealing twins.
However, they are useful to analyse the main trends of the martensitic transformations within a large number of γ grains.
It can also be noted that grains being less transformed often correspond to small grains or to annealing twins.
Thus, the orientation factor and probably the grain size influence the transformation rate of a γ grain.
Under these conditions, the model predicts during the initial stage of straining, a complete transformation of austenite grains, belonging to the Cube and Goss components whereas the grains belonging to {110}<111> and Copper components are not transformed.

In some alloys, minor elements such as carbon and boron were recently reintroduced in order to render the material more tolerant to problems related to large angle sub-grain boundaries with the objective of reducing the number of rejected blades.
This type of casting would result in an equiaxed (EQ)-grain shape.
This can be achieved by aligning grains along the stress direction [9].
To alter or remove grain boundaries, directional solidification is utilized to manufacture columnar grain or single crystal structures.
POLLOCK, METALLURGICAL AND MATERIALS TRANSACTIONS, Stabilization of Thermosolutal Convective Instabilities in Ni-Based Single-Crystal Superalloys: Carbide Precipitation and Rayleigh Numbers. 1960—VOLUME 34A, SEPTEMBER 2003

In order to prepare Fe-6.5wt%Si high-Silicon steel, a large number of investigations have been done.
As the rolling reduction is not enough to make the grain which is near the interface recrystallizing, so the grain is stretched along the rolling direction and presented fiber shape.
The coarse and equiaxed grains in coating layer indicate that both of the slab’s high temperature and the drastic plastic deformation make the continuous nucleation be possible on the grain boundary with decreasing of thickness of composite plate, but the fine grains just forming grow into coarsening ones quickly.
After high temperature diffusion annealing, the fibrous grains totally disappears and are replaced by coarsening equiaxed grains whose average size is 0.22mm.
Fig.3a shows that two grains are approximately equal to the sheet thickness, even one grain can run through the whole sheet.

In such earlier study, a large number of ECAP passes was employed to reach the total strain of e ~ 8, providing formation of almost uniform UFG structure just before rolling [8-10].
Moreover it has been shown [8,10], that cold rolling of such alloys, following completion of large number ECAP passes, can sometimes result in a drastic degradation of superplastic characteristics.
The volume fraction of the fine-grained component is less than 30 % and the average subgrain size was about 1 µm.
However, the particle density can still retain sufficient to prevent the rapid grain boundary migration, restricting grain growth even at high temperatures.
Both structures obtained were fine-grained with the nearly equal average grain sizes (8 and 9 µm in the samples after ECAP and rolling, respectively).

The ferrite grain size was calculated in accordance with GOST 5639-82 (RF State standard).
As is seen, it consists of ferrite-perlite grains.
The average size of grains in the surface layer makes 100-150 nm.
The graphs of dependence of the main crack length versus the number of cycles were plotted.
The number of cycles before the crack nucleation is increased approximately by 2 times as well.

The semi-products made from lead powder belonging to the grain size class of < 40 µm and oxide particles allowance have the highest mechanical resistance and the best corrosion behaviour.
In the second approach fine lead oxide particles PbO�Pb2O3 were added to the partially oxidised powder mixture belonging to the finest grain size class (< 40 µm).
Experimental In parallel, eight series of materials have been prepared and investigated in terms of mechanical and electrical properties: − series I: cast and extruded lead; − series II: cast and extruded Pb - 8% Sb alloy; − series III: extruded superficially oxidised lead powder of (56 -71) µm, grain size; − series IV: extruded superficially oxidised lead powder of (40 -56) µm, grain size; − series V: extruded superficially oxidised lead powder of < 40 µm, grain size; − series VI: extruded superficially oxidised lead powder of grain size < 40 µm, adding 0.5 % Pb3O4 (mass percentage); − series VII: extruded superficially oxidised lead powder of grain size < 40 µm, adding 1 % Pb3O4 (mass percentage); − Series VIII: extruded superficially oxidised lead powder of grain size < 40 µm, adding 2 % Pb3O4 (mass percentage); The superficially oxidised powder was obtained by the authors by air-atomisation, in an installation with horizontal jet.
The tensile strength of the partially oxidised lead powder samples of different grain size (series III, IV, V) is higher than that of the blank assays made from cast lead (series I). 2.
As the powder grain size is being refined (series III, IV, V) there is an increase in the number of fine particles of oxide dispersed in the lead matrix; consequently, there is a considerable increase in the mechanical resistance while the rigidity gets much improved (this is necessary for the gratings used as support in the lead accumulators) as compared to the materials in the series I and II; 3.

The degree of heavy metals leaching from soils, sediments and waste depends on a number of physical and chemical factors.
An increase in the level of elution of zinc and copper as the waste grain size decreases was observed.
The release of this element was lower at the pH value of 10.5 by 134 mg/kg (with the grain size <1 mm) and by 141 mg/kg (with the grain size <4 mm) than at the pH value of 3.
The release of zinc was also lower by 73 mg/kg (with the grain size <4 mm) and by 149 mg/kg (with the grain size <1 mm) at the pH 12 than at the pH value of 5.
In the case of a grain size <4 mm, copper concentrations were higher at the pH value of 10.5 than at other pH values.

The calculated grain mean sizes were 10-35 nm.
Moreover, these coatings have a large number of applications.
The results show that the undoped film (TO) is characterized by having a non-uniform grain distribution and the size of the grains is smaller than the grains in doped films, in contrast, FTO films has uniform distribution of grains and size of the grains is bigger than the grains in undoped films [16-17].
(b) Grain size.
As the doping increases, the grain growth also increases which in turn decreases the scattering due to grain boundaries.

Introduction There are a large number of irregular geometry and inhomogeneous particle size abrasives distribute on the surface of Vitrified CBN grinding wheel.
It can not truly reflect the actual grains of irregular shape.
This article used spatial random cutting plane method to establish the irregular shapes of grain model.
When at time of 800 us we can clearly see the abrasive grinding cutting edge has produced largely wear, a huge number of SPH particles were broken off from the irregular abrasive cutting edges.
However, the SPH method has advantage to statistics the number and size of the SPH particles which were worn.