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The microstructure of as cast state has relatively coarse grains (Fig. 1a), consisting of particles at grain boundaries.
After hot extrusion at 950 °C, grains are remarkably refined due to the breaking up of the grains and dynamic recrystallization, and the microstructure mainly contains equiaxed grains accompanying twin crystals (Fig. 1b).
A number of coarse particles are observed both inside the grains and at the boundaries.
Subsequent cold drawing cannot obviously reduce the grain size (Fig. 1d), which can be advantageous to retain high conductivity due to the decrease of grain boundaries.
This phenomenon can be explained that the number of crystal defects reduced largely due to the effect of restoration such as recrystallization (see Fig. 1) during solution treatment + aging.

At present, many scholars by measuring the number of practical and effective grain size and wear to create wheel topography models[1-3].
So the possibility generation of stochastic of polyhedral grains model was studied in this paper.
The second is number of effective abrasives edges on the surface of grinding wheel.
And irregular shape single grain was generated. (6) Sixth, moving single grain of local coordinates O' randomly in space within a range, and make it rotated a random angle.
Step 1 Step 2 Step 3 Step 6 Step 5 Step 4 Fig.3 CBN abrasive stochastic polyhedron shape modeling The number of polyhedral side on abrasive model can be controlled by the number of cut plane.

High Zn:Mg ratios also decrease particle size and increases the precipitate number density.
Fig.3 shows TEM images of precipitates at grain boundary and inside grain of the alloy in T6 condition after isothermal treatment for different time at 280°C.
It can be found that with the increase of isothermal holding times, there are more amount and coarser quench-induced η precipitates appearing at the grain boundaries (see Fig.3(a),(b),(c)) and even inside grain (see Fig.3(c),(d)).
And coarse η precipitates nucleated on Al3Zr dispersoids inside grains (as indicated by the arrow in Fig.3(d)), quench-induced η precipitates were surrounded by a precipitate-free zone.
a) b) c) d) Fig.3 TEM images of precipitates of the alloy in T6 condition after isothermal treatment for different time at 280°C (a) 2s, at grain boundary; (b) 60s, at grain boundary; (c, d) 600s, at grain boundary and inside grain, respectively Summary The nose temperature of TTP curve and the corresponding incubation period of the alloy, AA 7150 and AA 7B04 are about 290°C/4.5s, 320°C/2.6s and 335°C/0.1s, respectively, The nose temperature of the alloy is the lowest among three alloys and the critical time at the nose temperature is the longest for the alloy, which is obvious that the alloy has lower quench sensitivity.

n =NADmPFe / M (2) where NA, Dm and M are the Avogadro’s number, mass density and molecular weight of the corresponding sample, respectively and PFe is the number of iron atoms in the formula CoFe2-2xZrxMnxO4 (0.10.4).
It is formed by well conducting grains separated by thin poorly conducting grain boundaries [14].
The electrons reach a grain boundary through hopping.
If the resistance of grain boundary is large, the electrons pile up at a grain boundary and produce a polarization.
When the frequency of the applied field is increased, the probability of electrons to reach grain boundary decreases.

Fig.2 SEM pictures of SiC films with the thickness of 9μm As shown in figure 2, surface of the film has many grains.
The number of defects increases as the thickness of SiC thin films increase, and the grain size of surface becoming larger.
As is shown in figure 2, the average diameter of grains is about 2μm, but the grain’s diameter of SiC films with the thickness of 1.6μm is about 320.5nm.
Large grain size loosens the films, and the values of hardness and elastic modulus decreases.
This research was conducted under International Science & Technology Cooperation Program of China grant number 2013DFB10300.

It has not been observed any improvement or reduction of low cycle fatigue life in representation of total strain amplitude versus number of cycles to failure of grit blasted material in comparison with as-received material.
Number of embedded particles is related to blast pressure, angle of incidence and size of particles [6].
The macrostructure was composed of dendritic grains with carbides, eutectics and shrinkage pores (see Fig. 1a).
An average grain size was 0.66 ± 0.1 mm established using linear intercept method.
Results Surface relief and fracture surface observation Fig. 1 (a) Coarse dendritic grains with detail of pores (b) as-received surface with detail of precipitate morphology (c) grit-blasted surface with embedded particles (see arrows) (c) Fig. 1 shows SEM micrographs of surfaces of test specimens.

Residual stresses can be classified by their extent. 1st order or macroscopic stresses are in the range of the component size; 2nd order or microscopic stresses vary between individual grains and 3rd order or submicroscopic stresses vary within the grain.
E (Young modulus) and n (Poisson number) are the elastic parameters of the material.
Tensor measurement Microstructural effects X-ray diffraction techniques require fine grained, isotropic samples.
These requirements are fulfilled for fine grained powders.
The ragged reflections are due to the small number of grains that contribute to the peak (Fig. 7 b), while the differing intensity of the two detection directions is caused by the texture of the component (Fig. 7 c).

The larger grain size and higher density ceramics body will contribute the good dielectric properties.
A number of studies have been carried out to overcome this problem.
As the sintering temperature increased from 1000 ºC to 1080 ºC, a dense with large grains (0.1 - 0.9 µm) was developed at 1000 °C to (0.3 µm - 2.5 µm) at 1080 °C.
Extra thermal energies caused abnormal grain growth occur and decrease the density of the sample due to the more pores trapped inside the grain which cause intergranular porosity increase.
The larger grain size and higher density ceramics body will contribute the good dielectric properties.

The max stress was 275MPa; the stress ratio was 0.2; and the number of each group was 6.
The size of grain structures is closely related to the cooling rate.
The columnar grain structure can be attributed to directional cooling, and the direction of the grain growth must be along the largest temperature gradient during solidification.
Some of the precipitated rhabditiform compound became the nucleating center, and the others were pushed to the crystallization front edge, which impeded the growth of the grains.
This is because that the columnar crystals whose primary dendrites are very long, slender, and perpendicular to the clad interface are easy to split along the grain boundary under the tensile stress.

Because anti-permeability strength of cohesive soil (refers to plastic index more than 7, viscous grain content more than 10% of fine-grained soils) and cohesiveless soil one are very different, filter layer particle composition request are also not identical.
If penetrative cracks don’t exist in cohesive soil along seepage direction, the grain needed filter layer can be very thick, if grit or gravel of D20<10mm are used, it have enough safety.
Determining principle for the number of filter layers. multilayer filter can guarantee each layer filter material without seepage damage.
The number of filter layer is mainly decided by two factors: the first is the size of lower drainage layer, the second is each layer thickness.
The second, third layer design according to Eq.1 can make filter layers number less than three , and can guarantee each layer has good work performance