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The usual methods for determining grain boundary diffusion coefficient measure the triple product P=sδDb, where s is solute segregation factor defined as a ratio between grain boundary and the lattice solute concentrations [2], δ is grain boundary width and Db is grain boundary coefficient.
Number of angles was from 50 to 200 per each sample.
As a result grain boundary diffusion coefficient will be smaller.
The analysis showed the presence of precipitates on the grain boundary.
It seems that iron does not affect significantly on kinetics properties of Cu grain boundaries with an exception of iron grain boundary diffusion.

Ultra-Fine Grained Al-SiC Metal Matrix Composite by Rotary Swaging Process S.
From Fig. 1(b) and 1(c) one can see that the microstructure is becoming more uniform as the number of passes increases.
These are interpreted as steps created on the grain boundary (surface) by the movement of a number of dislocations in the same slip plane.
In each stress cycle it is very probable that a large number of dislocation move across the grain from boundary on the same slip plane leading to a displacement in multiples of burgers vectors of the dislocation.
The spacing between the dislocations being less than 100nm indicates that it is a high angle twist boundary created as a result of relative rotation between grains which could have been a single grain with a low angle sub-grain boundary created in the initial stages.

There was a coarse-grained ring in the aluminum alloy extruded bar.
Therefore, the surface grains of extruded aluminum alloy bars are more likely to recrystallize, and some of them even swallow up the surrounding grains.
However, it grows rapidly and forms coarse-grained structure, named as coarse-grained ring.
The fracture dimples of the tensile samples are shallow and the number of dimples is small, as shown in Fig. 4 a).
The fracture dimples of the tensile samples are deep and the number of dimples is large, shown in Fig. 4 b).

The distribution of crack number per specimen with 4 notches for crack depth is shown in Fig.2.
The GBCD control decreased the maximum crack depth in C-doped steels, while the GBCD control decreased the number of IGSCC in C-free steels.
Therefore, IGSCC propagates along higher energy grain boundaries.
An EPR test revealed that the reactivation ratio of C-doped and C-free steels were 34% and <1%, Grain boundary character; Fig.1 OIM maps of cross section around IGSCC in a GBCD controlled C-doped steel. 200µm (a)SEM image (b)IQ map (ｃ)GBCD map Notch bottom Notch bottom Notch bottom IGSCC Lower IQ-value zone Random Σ1-29 Grain boundary character 0 1 2 3 4 5 0 1 2 3 4 5 Fig.2 Effect of carbon content and GBCD control on distribution of the number of IGSCC (a) C-doped Number of IGSCC per specimen Depth of IGSCC, d/µm 0 100 200 300 400 500 600 700 800 900 1000 1100 1200 (b) C-free GBCD uncontrolled GBCD controlled respectively.
The IGSCC predominantly propagated along random grain boundaries.

Cases with the same grain size have the same grain properties including grain distribution and grain orientations.
Composite model combining grain interiors and grain boundaries with grain size of 150 and 300 µm.
According to Eq.12, the grain boundaries with grain size of 300 µm is about 1.6 times as thicker as them with grain size of 150 µm.
Since the thickness of grain boundaries in the composite model is the size of individual elements, their elements number reflect this relationship.
In addition, the number of shear bands is decreased.

It can be seen that there exists a sufficient number of visible particles, which are shown in yellow in Fig. 1 (a) for one grain.
It can be also seen from Fig. 1 (a) that there are a number of particles that are located in grain interior.
Although this process greatly reduces the number of diffraction spots related to a particular grain, there are still a number of retained diffraction spots for a particular grain.
Since grain 1 is fairly large compared to Grain 2, a greater number of grains are illuminated while the X-ray pencil beam intersected Grain 1.
Black lines super posed on the strain contour maps indicates grain boundaries, and white figures indicate grain number.

Many grain and oil depots have been established.
For instance, total investment of Da Lian Nrth Liang grain depots are 82 million RMB; 15.5 million was invested for Shanghai Wai Gao Qiao grain depots, and also 10 million RMB for exlarge construction work of Xin Sha grain depot in Guang Dong Province. ②Big floor area is needed.
One group is composed by grain depots, oil depot, delicate railway and dock, deep processing for the grain and oil factory, test office.
The arrangement of sand drains are quincunx with diameter of 0.4 m ,distance between drains of 2.5m ,length of 18m and the total number of sand drains is 283.
A large number of practical projects show that the ground bearing capacity of the region can improve 15 to 30 kPa by vacuum preloading method.

During the past few decades, A Large number of research on dilatancy of coarse-grained soil have been carried out by many scholars abroad, and have obtained certain achievements[2-8].
And meanwhile, Isotropic consolidated-drained triaxial tests is performed for overburden material of Shuangjiangkou earth dam whose relative density is 0.8(the test number is SJK2-CID).
In-situ compaction of coarse-grained materials[M].
Characteristic of dilatation of several kinds of grained soils[J].
Engineering properties and applications of coarse grained soil[J].

Normal grain growth is associated with the coarsening of grains with the {0001}< 0211 > orientation.
It is recognized that recrystallised grains do not nucleate as totally new grains.
Grain growth after primary recrystallisation.
Grain growth after primary recrystallisation.
By contrast, the development of the {0001}< 0211 > texture component takes place by a discontinuous recrystallisation process with the migration of high angle boundaries which absorb defects of the deformed matrix and leave behind almost defect-free new crystals. 0 0,02 0,04 0,06 0,08 0,1 20 30 40 50 60 70 Image quality Number fraction (0001)<10-10> (0001)<11-20> 0 0,02 0,04 0,06 0,08 0,1 10 20 30 40 50 60 70 Image quality Number fraction (0001)<10-10> (0001)<11-20> Figure 4.

After 2 passes, the number of recrystallized grains had increased the distribution of recrystallized grains and the precipitated phase was coincident.
The yield strength then decreased with further increase in the number of passes.
As to the yield strength, above 4 passes, the grain size of matrix did not change with the increasing number of passes, while, the size and amount of the second phase increased.
Summary During the first 4 passes, the grains of the GW103K alloys were refined gradually with the increasing number of passes.
The second phase particles precipitated preferentially near the grain boundaries and grew gradually with the increasing number of passes.