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The grain size decreased with increasing strain rates at 750k. 1.
The microstructure consists of elongated grains with serrations developed in the grain boundaries and newly formed equiaxed grains of different sizes, indicating dynamic recrystallizatioin (DRC) occurred during hot compression deformation at strain rate of 0.01s-1 (Fig3(a)).
The coarsening of precipitation phases at grain boundary could pin the grain boundary, and prevent it from fast migration, so both the newly formed recrystallized grain and old grain would not grow very fast.
That is why the grain size decreased with increasing temperature at 750k.
Acknowledgement It is a project supported by natural science foundation of shanxi province China (project number: 2009011028-1; 2011011021-1).

The model of abrasive grain’s wear.
Abrasive grains move at a constant speed.
Fig.3 The relationship between grinding force and surface roughness The reduction of surface roughness is directly related to the number of active grains Ng and the shape of the grains.
Under these conditions, abrasive grains are worn quickly or can be extracted from the bonding phase which may decrease the number of real active grains Ng.
New grains are involved in grinding.

These boundaries correspond to high-angle grain boundaries.
The area fraction of Cube oriented grains was largest when the area fraction of recrystallized grains reached 100 % in each alloy.
Therefore, Therefore, the <0 0 1> grains shown in Fig. 9 are considered to recover more easily and grow more preferentially than other grains.
Cube oriented {0 0 1}<1 0 0> grains in aluminum alloys is considered to be able to grow preferentially similarly to <0 0 1>grains.
In　MZ alloy homogeneized at 590 ℃, the number of recrystallized grains immediately after the deformation is smaller than M alloy.

In order to clarify this problem, it is advisable to perform experimental research under conditions where the number of 'free parameters' affecting this transformation is minimized.
The range of potential disorientation angles was binned into intervals of 1.25o into which the number of disorientations across the recrystallization front corresponding to a given angular interval was counted.
The columns contain the explicit number (‘Counts’) of experimental axis in a class and the fractions after accounting for the differences in the areas of regions and the impact of crystal symmetry (‘Distr.’).
The results allows us to draw the following conclusions: · For Ni and Cu-2%Al and both initial orientations at the initial stages of recrystallization, the appearance of a specific number of new orientation groups of new grains was demonstrated.
This facilitates ‘the orientation stability' of a new grain growing into the as-deformed structure

The optical micrographs reveal the formation of fine grains.
Thus, a fabrication process is required with proper parameters to increase the interfacial bonding strength and to decrease the number of pores and thus mechanical properties will be improved.
Densification for ECAPed specimens increases with increase in milling time along with number of passes.
As, the number of passes increases for the20hr and 35hr milled powder, the hardness increases significantly.
Langdon, The principles of grain refinement in equal-channel angular pressing, Mater.

Fine lath martensite was obtained by the “zero time holding” quenching due to the smaller austenitic crystal grain and the uneven distribution of the carbon concentration in austenitic crystal grain.
Therefore, grains are fine and grain boundary area increases.
Especially when heating temperature at 940℃, the austenitic grains grow up obviously.
Austenitic grains become coarse gradually if grain growth speed V increases.
Microstructure analysis shows that a small number of ferrite exist in the sample quenched 860℃.

The performance of a TiO2 photocatalyst is strongly dependent on a number of other structural factors such as crystal phase as well as grain forms and the degree of crystallinity of the TiO2 particles [5].
The solvents have affected the forms and sizes of the grains in the samples.
This process can influence the grain to growing up.
Different solvents affected on the grain size and morphology of samples.
This research is funded by Vietnam National Foundation for Science and Technology Development (NAFOSTED) under grant number 103.02-2011.12.

Microcracks propagation is evidently impeded by grain boundaries at low stress level and high stress ratio.
Detailed test procedures (stress level and stress ratio) and number of specimens are shown in the Table 2.
Microcracks slow down or stop near grain boundaries.The fact that microcracks have difficulty in traversing grain boundaries means that the crack plane has some favorable orientation with respect to the slip plane.
Microcrack propagation was clearly affected by the orientation of grains.
(4) Microcracks slow down or stop near grain boundaries.

In order to investigate effects of a grain size of the source diamond, EDM cutting experiments were conducted on the EC-PCD specimens of 4 different grain sizes.
In the case of S-PCD, the cutting speed for the 25µm grain size was lower by 15% or so compared with the10µm grain size.
In both cases of 10µm and 25µm grain sizes, surface roughness value of the EC-PCD was smaller than that of the S-PCD by 40% or so, and the EC-PCD of 25µm grain size after EDM cut showed the surface roughness identical to the case of the S-PCD of 10µm grain size.
In the SEM image of the S-PCD surfaces, a number of the pits created by preferential removal of the cobalt can be observed.
This phenomenon becomes prominent as the diamond grain size gets larger.

The quality of ductile iron increases with the number of the graphite spheroids.
The quality of ductile iron increases with the number of the graphite spheroids.
This model treats a given number of polycrystalline grains having different lattice orientations.
The calculations are based on the modelling of the processes which occur inside and between grains.
As the result, the internal stresses for grains of different orientations and for the whole sample are predicted.