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Unique features of ultrafine-grained microstructures in materials having low stacking fault energy Jenő Gubicza1,a, Nguyen Q.
It can be seen that the size of the recrystallized grains is ~1 µm.
In severely deformed polycrystals, the magnitude and direction of the internal stresses change from grain to grain, so that the probability of annihilation of dislocations depends upon their specific locations within the specimen.
By increasing the numbers of passes up to 8, the mean dislocation density measured immediately after ECAP is increased and accordingly the rate of recrystallization should be faster after larger numbers of passes.
With increasing numbers of ECAP passes, there is an increase in the contribution from twinning which appears to facilitate recrystallization.

Grain sorghum is a kind of crop that has been planted widely in China and even in the world.
Materials and methods Modification of grain sorghum stalk The grain sorghum stalk was collected from a local farm.
The grain sorghum stalk was modified following the method of Li et al [13].
Langmuir isotherm model assumes monolayer adsorption on a surface with a finite number of identical sites.
As the increasing of pH, the number of positively charged sites decreased and the number of negatively charged sites increased, which favors the removal of the cationic dye.

The size of the primary silicon grains decreases and the grain number density rises with the increase of the magnetic strength maintaining the magnetization force unchangeable.
Thirdly, the solidification structures of longitudinal section of the solidified samples were examined at first, then tested the mean diameter (d0) and the particles number density (NV) of the segregated primary silicon grains by the quantitative method in morphology.
Furthermore, with the increment of the magnetic flux density, the difference of the grain size (to define ,and are the maximum and minimum diameter of the grains, respectively) decreases, but increases the number particle density.
ML+2MS is called as strength field magnetic quantum number. , called as Bohr magneton.
(2) Keeping the magnetization force same, the sizes of the primary silicon grains in segregated layer decrease with the increment of the magnetic flux density, but the particle number density increases

Stress Induced Grain Boundary Motion in Al bicrystals Dmitri A.
Usually, starting from one location at the initial boundary these grains develop into groups of sub-grains separated from each other and the original consumed grain of the bicrystal by low angle boundaries.
The boundaries between sub-grains and the growing grain remain stable and with progressing migration of the original grain boundary the sub-grains become wider (Fig. 4).
Apparently, the formation of new grains observed in the current experiment is facilitated by the nucleation of a sufficient number of lattice dislocations by the grain boundary during its stress driven migration coupled to shear deformation.
Then, these dislocations build walls and finally turn into sessile boundaries between the new grain and the growing grain of the original bicrystal and the moving low angle boundary that separates the new grain from the consumed grain of the original bicrystal (Fig. 4).

Grain boundaries were categorized as Low-Angle Grain Boundaries (LAGB - Σ1), Σ3 grain boundaries, and Σ3-related variant grain boundaries (Σ9, Σ27).
The grain boundary width was 1 pixel.
This is a direct consequence of the reduced number of grains per unit area.
The monotonic variation of grain boundary mass with grain size for both random and Σ3 is evidence that the grain size (D) is a characteristic length scale for the topology of the grain boundary clusters.
The effect of annealing time on the distribution of the number density of the Σ3 n cluster masses (M) is summarized in Figure 4.

The production of fine grained materials by SPD, led to a large number of investigations focusing on the microstructure development and related to mechanical properties.
Compared to other SPD processes the HPT technique offers a large number of advantages, as stated in [4].
Transmission electron microscopy (TEM) was used to evaluate the ultrafine grain microstructure evolution with respect to position on deformed disc and the number of turns at corresponding εeq.
The ufg grain substructural features in disc edge support this selective growth of fine grains, as is seen in Fig. 4.
Specific behaviour resulted as strain was increasing with number of turn.

Abrasive Grain Models.
Thus, the value of the grain volume has an influence on the distribution and consequently on the number of grains in the grinding wheel surface [5], which follows from Eq. 1 [7].
The number of grains in a defined volume NV can be calculated from the abrasive concentration C, the density of the cutting material ρg and the volume of the abrasive grain Vg.
While using the same grain size, the shape of the abrasive grain has significant effects on the grain's volume and the number of grains in a defined volume.
The distribution model and the concentration characterize the number of active cutting edges.

In terms of cycles, Stress Life is based on S-N curves (Stress – Cycle curves) and has traditionally dealt with numbers of cycles greater than 105 cycles inclusive of infinite life.
In non-constant amplitude loading, cycles with very small alternating stresses may be present and may incorrectly predict too much damage if the number of the small stress cycles is high enough.
Figure 3 presents a S-N curves of alternating stress versus number of cycles to fracture for diamond (a) and metal bond (b).
For a grain size of 28/20 µm, with the same force parameters of grain and workpiece interaction, the grains will continue to be retented in the bond (figure 7b).
Fatigue life for grain-bond system for 20/14 µm grain size a) b) Fig. 7.

After acquisition of the temperature signal, it can be inputted into the microcontroller, and this should be obtained by giving corresponding software processing which derived from a large number of experimental data and the process of fitting. 2.5.
Resistive grain moisture content determination method[J].
Grain and oil processing and food machinery, 2005 ,2 : 66-69
A kind of sensor measuring grain moisture content [J].
Grain moisture measuring instrument based on capacitive sensor [J].

the strain tensor, the texture development and the grain subdivision mechanisms.
The reduction of shear flow stress in the band from Gτ to ( )NG DB 1 δ−τ=τ can be estimated from the local modified Taylor factors in the grain and the DBs by G DB N M M =δ , where the modified Taylor factors are based on the minimum number of simultaneously acting slip systems necessary to accommodate the actual strain.
Where DG is the size of the grain in which the DB may form.
It is also clear that by reducing Mr by creation of Σboundaries, deformation banding may still be a deformation mechanism at very high strains when the grain size has reached sub-micron sizes, i.e. one can expect to observe an increasing number of twin configurations and CSL boundaries at very high strains (from 2 to 8 ECAP passes) [3].
The number of twin boundaries and other CSL configurations are observed to increase with accumulated strain (and increased shear stress)[3,++zuh twins].