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However, the previous process takes place retarded in comparison to fully austenitic steels [7] due to the smaller number of internal austenite-austenite grain boundaries.
The crystallite size of the ferrite grains and/or subgrains was determined by using a grain tolerance angle of 0.5°.
The IPF coloring plot in Figure 3a shows small recrystallized grains at prior austenite-austenite grain boundaries.
As can be seen in Table 1, the grain size of the ferrite grains in the starting material is large (~700 µm²) and the majority of grain boundaries is of high angle character.
This results in a fine grained microstructure consisting of (sub)grains at 1100°C.

In this study the EFEmax parameter is used for selecting the wheel grain.
The number of repetitions of the experiments was n=30.
They are made from microscopic corundum grains (synthesis corundum) containing 50% of sol-gel (SG) grains in the mixture of aluminum oxide A.
As follows from Table 2, with a decrease in the number of meshes (or an increase in grain sizes) from 60 to 46, the experimental and predictable medians are monotonically reduced within the accuracy quality class TFE: for the main parameter EFEimax - from 13 to 12 μm (TFE7); for EFEia – from 9.46 to 7.96 μm (TFE6) and EFEiq – from 9.70 to 8.41 μm (TFE6).
It was revealed that the HPW grain based on the 5SG grains has a much greater impact on the process stability than on the position measures.

Although a few number of publications on the microstructural evolution occurring during warm deformation of plain carbon steels have been reported [14, 15].
At this stage, ultrafine grains, even though few in number, are formed at the original grain boundaries and the grains aspect ratio increases along the torsion direction.
Very fine equiaxed ferrite grains surrounded by HABs were generated along the initial ferrite grain boundaries, even though they were small in number.
Additionally, there are a number of incomplete high angle boundaries, i.e. isolated high angle grain boundary segments present in the larger ferrite grains.
This indicates that the grains were formed by a process of fragmentation / subdivision of initial grains.

It can be seen that, second phase on the grain boundary was dissolved into the grain.
The deformation texture interacted the banding grain, so the grains were refined once again.
During the deformation, intense shear deformation of ECAP can produce a large number of dislocations.
Fig.3 Microstructures of ZK60 before and after ECAP ( with different pass times): (a)0 pass (b) 4 passes (C)6 passes Fig.4 Dislocations in the grains Fig.5 shows the XRD patterns of the samples pressed with different number of passes.
Since in the early deformation, a large number of dislocations produced and hindered the deformation, so the sample hardness increased remarkably.

The TiAl alloy with fine grain via reactive sintering was obtained.
The microstructure of TiAl intermetallic alloy shows equiaxed grain that the average grain size is 5~10µm (Fig.8).
The grain size of TiAl alloy has been grown slightly but the shape of the grain is not changed.
The grain size is average 8µm.
Acknowledgements This work was supported by the Postdoctoral Foundation of Heilongjiang Province under grant number AUGA41000551.

Scheme of the grain configuration and original SE images of different regions in the Ni50.8Ti49.2 alloy showing the evolution of the Ni4Ti3 precipitates in size and distribution from the grain interior (GI) to the grain boundary (GB).
Ni4Ti3 precipitates in the GI region show a fairly random distribution with no regional preference for size or number density within the reconstructed bulk, while the precipitates in the GB region reveal a strong size variation along the slicing direction (Z direction), which is also the direction towards the grain boundary.
Number, number density, volume ratio and arithmetic mean of all listed precipitate parameters for the two selected regions.
The precipitates in the grain interior (GI) region with larger size but smaller in number show a fairly random distribution without any regional preference of volume or number density.
The smaller but large amount of precipitates in the near grain boundary (GB) region show an obvious decrease in size and significant increase in number when moving towards the grain boundary.

EBSD analysis revealed that absence of B induces fine ferrite grain size and many high angle grain boundaries. 1.
The grain identification angle is 5°.
As the amount of B increases, the number of high angle grain boundary (misorientation angle >15 o ) decreases.
It seems that the fine grain size and a large number of high angle grain boundary in steel B0 are attributed to large volume fraction of dynamic recrystallization.
In addition, the absence of B led to decrement of ferrite grain size and increase of high angle grain boudnaries in hot-rolled high strength IF steels.

In recent years, people have proposed a number of model against RBAC, such as RBAC96[1], ARBAC97[2], ARBAC02[3], RHA4[4] and HARBAC[5] etc.
In Section 2 we present the proposed fine-grained RBAC model.
In this paper, we propose the fine-grained RBAC model as follows: 1.
Fine-grained RBAC requires fine-grained resources; therefore the proposed RPA can identify access control by URI resources.
Class diagram of fine-grained RBAC architecture.

The average grain size of ZnO was 13.3 µm.
In addition, the presence of the ZnV2O4 spinel phase at the grain boundariesmay also play a role in controlling the ZnO grain growth.
As can be seen, the average ZnO grain size is 13.3 µm, it shows very normal grain growth of ZnO.
At the same time, it is clear that the grain boundaries.
However, it is also clear that the pores exist at the grains and grains interior, which are bad for the electrical properties of ZnO varistor ceramics.

This work is funded by the National Science Foundation under Grant Number DMR-0517351.
Titanium alloys have a number of properties that make them desirable for many applications.
Large-grained alloys (>200 µm) show extensive slip and twinning, while small-grained alloys (<100 µm) deform solely by slip.
%V alloy at 95% YS as a function of grain size.
It has been found that a number of factors affect twinning during low temperature creep.