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The plasticity can be enhanced with the increase grain size, the elongation ratio is 80% with 35µm grain size, but the elongation ratio is 59% with 5µm grain size.
There are three different curves for different grain size.
One hand the frenquency of misorientation angle between 35 and 55 is different, that of grain size 5µm is higher than 0.01 while that of grain size 35µm is below 0.01, On the other hand the frenquency of misorientation angle between 55 and 60 is also different. that of grain size 5µm is only 0.5 while that of grain size 35µm is so high to 0.12.
As we see, the Grain is mainly high angle grain boundaries (> 15 degrees), the misorientation of grain is 60 DEG holds the very great proportion.
The twin formed in the annealing experiment is the twin, so the difference between the orientation of grains in 60 degrees, so obviously high frequencies appear 60 degrees near is the annealing twins[11], the number when grain size is 35µm reached 61%, while the number when grain size is 5µm is only 45%.

The average grain size of the alloy was reduced from ~150 mm to a grain size in the range of ~500 nm through processing by HPT.
It is observed that an increase in the number of turns leads to a more pronounced refinement of the structure.
The results can be converted into hardness as a function of the equivalent strain by using the correlation between equivalent strain, , and distance to the disk center, r, the disk thickness, h, and the total number of turns of HPT, N: (1) Figure 4 shows the evolution of hardness as a function of the equivalent strain.
It is also observed that the distributions of grain sizes are similar in the materials processed by different numbers of turns and subjected to a similar annealing treatment of 5 min at 250° C despite the difference in initial grain size distribution.
The initial coarse grain structure, with a grain size of ~150 mm, was successfully refined to a grain size of ~0.5 mm after HPT.

It is found that the initial coarse grains of Ti-50.9at%Ni alloy were refined into submicron grains, smaller than 0.5 um in size, after eight passes ECAE at 500ºC.
Martensitic transformation temperatures decreased remarkably after one pass ECAE and more gently with increasing the pass number of ECAE.
Many long blocks were divided into fine equiaxed grains or subgrains(Fig.1(c)).
After four passes ECAE, no grains or grain boundaries can be identified under optical microscope.
Martensitic transformation temperatures decreased remarkably after one pass ECAE and more gently with increasing the pass number of ECAE.

The influence of cooling rate on grain size of Mg-Zr alloys was also investigated.
This exceptional grain-refining ability of Zr has led to the development of a number of commercially important sand casting creep-resistant alloys[5].
Their dimension is as big as grain size of near 200μm.
Summary of morphology and dimension of Zr-rich core Zr addition,% Mould Morphology of Zr-rich Diameter of Zr-rich, μm Morphology of grain 1.20% copper round 7.54 fine equiaxed grain steel Round + rosette-like 11.3 fine equiaxed grain Sand 1 round 19.1 equiaxed grain Sand 2 round 29 coarse equiaxed grain 0.70% copper equiaxed grain steel equiaxed grain Sand 1 equiaxed grain Sand 2 rosette-like 200 equiaxed grain 0.30% copper Columnar grain steel Columnar grain Sand 1 Columnar grain Sand 2 Columnar grain The grain sizes for the alloys solidified in four moulds were given in Fig.5.
The grain size increased with decreased cooling rate.

The variations in the structure of the material are obtained by changing the load applied on the roller and by increasing the number of passes.
Microstructure describes the grain refinement in ARB processed materials.
ARB of dissimilar alloys shows layer thinning and grain refinement [6].
Ultrafine grain size was achieved through ARB process.
Bonding between the layers was successful only after a required number of cycles.

Manufacturing and Experimental Research of Fine Grain Diamond Grinding Wheel Based on Magnetic Field Controlling S.H.
The manufacturing and dressing of fine grain diamond grinding wheel based on magnetic field controlling (acronym FGDWMC) were introduced.
Fig.5 is the SEM photo of the surface of plain wheel，from which the grains aggregation can be seen.
Table 1 Grinding Conditions Grinding Types Grain Size Grinding Wheel Dia.
Acknowledge This research is sponsored by the NSFC (Grant No. 50975084) and the National Key Technology Program (Project number 2010ZX04001-151).

The upsetting and extrusion processes are repeated over and over again till the desired number of cycle is reached.
This deformation pattern becomes predominant with increasing number of RUE cycle (Fig.2d-f).
Macrostructure of OFHC Copper subjected to increasing number of RUE cycles.
With increasing the number of RUE cycle, the distribution of these fine grains increases at the expense of coarser grains.
Microstructures at various regions with increasing number of RUE cycles Microstructures shown in Fig.4c-f provide direct evidence to the evolution of new ultrafine grains as per MSB model during RUE.

Formability of ultrafine-grained steel is examined by applying to form a M 1.7 micro screw using these ultrafine-grained steels.
Much of the work has been on the development of ultrafine grained steels.
Nominal Stress Therefore, ultrafine grained steels are expected to have higher reduction in area, compared to conventional grain size ferrite - pearlite steels.
Although some sub grains and ferrite grains elongated in the rolling direction have been retained, a large number of equiaxed ultrafine ferrite grains surrounded by high angle grain boundaries were observed.
The structure is occupied by fine equiaxed ferrite grains.

Although their specific form is complex, it is not difficult to calculate their coarse-grained average.
Coarse-Grained Average of Field Variables Any macroscopic field variable and its corresponding microscopic or mesoscopic field variable can generally be related by coarse-grained averaging in space,
For example, the microscopic mass density field is , (9) where and are the mass and position of the k nucleus or electron respectively, and N is the total number of nuclei and electrons in the system.
It is obvious that the macroscopic mass density field ρ is equal to the coarse-grained average of .
Like velocity, displacement and strain are not coarse-grained averages.

Grain boundary liquid grooving process takes place during the contact of solid phase with the melt.
Introduction The problem of interaction between solid and liquid metal phases was described in a number of theoretical and experimental works [1,2].
It is well known that liquid-metal grooves form on the liquid-solid interface at its intersections with grain boundaries (GBs).
The average grain size of copper samples was about 40 μm.
Straumal, Grain boundary phase transitions, Nauka publishers, Moscow, 2003