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The average grain size of this sample is 26nm.
Number density, chemistry and total solute distribution are also shown (f-h).
Turning to the solute dispersed in the intragranular regions, our analysis of cluster number density is provided in Figure. 3f.
The probability of the occurrence of random solute clusters was assessed and subtracted from the experimentally observed number density.
Combining the information on chemistry and number density, we find that 39% of the solute in the alloy is involved in atomic clustering and most of this is allocated to the modal clusters of size 8-12 atoms.

Keywords: brittle fracture, intergranular fracture, the strongest-link theory, grain boundary engineering, grain boundary character distribution (GBCD), grain boundary connectivity. 1.
However, thanks of the advent of the Orientation Imaging Microscopy (OIM) [10], we can very quickly determine by the computer-assisted OIM, the orientations of large numbers of individual grains, the size and shape of grains, and the character of individual grain boundaries.
Moreover we can obtain statistical information on the grain orientation distribution, the grain boundary character distribution (GBCD), grain boundary geometrical configuration and the grain boundary connectivity which define "the grain boundary microstructure", in addition to the average grain size and the grain size distribution widely used to discuss microstructural aspects of metallurgical phenomena in polycrystals.
So the toughening by grain boundary engineering will be more effective when polycrystalline materials have very fine grain size or even nanometer grain size. 4.
Achievement of Grain Boundary Engineering for Brittle Fracture Control Until recently, a rapidly increasing numbers of achievements have been made by the grain boundary engineering, since the early works on brittle fracture control in iron-6.5wt.

The grain refinement is achieved more effectively as the temperature for ECAP is lowered and the number of ECAP pass is increased.
Three important conclusions arise: first, the grain is more refined and distributed more homogeneously as the number of ECAP passes increases; second, the grain refinement is more effective as the ECAP temperature is lowered; and third, in order to lower the ECAP temperature without breaking the sample, it is necessary to obtain a homogeneous and equiaxed grain structure before ECAP.
Figure 2 plots the variation of ductility as a function of the number of ECAP passes.
Fig.2 Dependence of elongation on number of ECAP passes.
Fig.3 Dependence of elongation on number of ECAP passes showing effect of subsequent annealing. 0 1 2 3 4 0 0.1 0.2 0.3 0.4 NUMBER OF ECAP PASSES TRUE STRAIN T = R.T

The bulk ultrafine-grained (UFG) materials usually show superior mechanical properties.
First, the exponent of the inverse grain size is given by p = 2.
In practice, the hardness decreases constantly with increasing numbers of HPT turns.
Fig. 4 Variation of the values of m for the Zn-Al alloy before and after HPT for different numbers of turns.
Over this wide temperature range, the submicrometer grains accelerate the level of grain boundary sliding leading to high ductility and plasticity in the Zn-Al alloy.

The microstructure of initial CCM alloy contains equiaxed grains with a grain diameter of approximately 50 mm and twins.
The clear grain boundaries of equiaxed grains and twins disappear after HPT processing at a rotation number, N, of 10.
The grain diameter of equiaxied grains is approximately 50 mm.
On the other hand, the clear grain boundaries of equiaxied grains and twins are not observed in the CCM alloy subjected to HPT processing as shown in Fig. 2 (b).
The clear grain boundaries of equiaxied grains and twins, which are observed in initial CCM alloy, disappear after HPT processing. 2.

Effect of various numbers of passes through ECAP (Equal Chanel Angular Pressing) die on microstructure and properties have been evaluated.
It is clearly seen effect of improving both yield stress Re as well as tensile strength Rm with number of passes through the ECAP die.
It is also seen the positive effect number of passes through on the grain size that decrease more twice after two passes through.
Microstructure investigation were carry out only using light microscopy as the grain size of the cast was quit large (corresponds grain size number G0) and it is documented both for virgin state and for ECAP samples in the Fig. 4 and Fig. 5.
Change in the grain size can be also expressed using Grain size number according to ASTM E 112 that changed from G0 for cast state to G2.5 – G3 after two passes through, it means refining about 50 %.

processed by HPT as a function of the number of turns.
It is seen that the Hv at the center increases sharply with the number of turns sharply for a small number of turns, less rapidly after 20 turns and reach a saturation value after 40 turns.
The evolution of the microstructure with the number of HPT turns was investigated by TEM.
Fig. 3 (a)-(c) shows the bright field images of disks with different number of turns.
For a large number of turns the estimated values of Hv are higher than the measured values.

In order to lower interfacial stresses between copper and nickel, the microstructure of nickel was controlled to consist of grains with a mean size of 15 nanometers.
In the Cu electrodeposit, the as-deposited texture characterized by a relatively high <100>//ND and twin components transformed to be diffuse due to grain growth during annealing above 300oC.
This is attributed to a large number of twins conducting the as-deposited microstructure.
On the other hand, in the Ni electrodeposit, grain growth that takes place during annealing above 250oC corresponds to abnormal grain growth in terms of the scale change of the grain size.
This grain growth also transformed the as-deposited texture of strong <100>//ND into a diffuse texture.

Thus, the total number of microscopic slips is estimated as the total number of dislocations piled up at the grain boundaries as described by 　
First, as the hot rolling and annealing, grains with a small total number of microscopic slips might obtain a preferred orientation.
We suppose that the crystal orientation of the statically recrystallized grains would be the same as that of the grains with a small total number of microscopic slips.
The total number of microscopic slips is estimated as the total number of dislocations piled up at grain boundary.
The preferential recrystallization orientation that is the same as that of the grains with a small total number of microscopic slips indicates bulging at a high-angle grain boundary.

Sodium hydroxide was used to modify distillers' grains (DG) assisted by microwave in order to comprehensive utilization of distillers' grains (DG).
China is a big liqueur producer, a large number of distillers’ grains, a co-product of a dry grind ethanol process, would come out.
Fig. 1 The SEM photographs of distillers' grains and modified distillers' grains Infrared Analysis.
The FT-IR spectrum of DG and MDG display a number of absorption peaks (Fig.2).
Fig. 2 FT-IR of distillers' grains and modified distillers' grains Effect of Sodium Hydroxide Concentration.