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A number of the specimens used for the strength tests ranged from 10 to 30.
The characteristic strength values and the Weibull moduli have been determined by a linear regression and by Maximum Likelihood Method both applied to the following y-x dependence resulting from the Weibull theory in the form axmy += ,                 − = fP y 1 1 lnln , ix σln= , 0lnσma −= , � i Pf 2 12 − = , (4) where fP is probability of failure, � is number of measured values of the strength iσ related to the i-th measurement, and an increase of the natural number i is required to correspond to an increase of a value of iσ , i.e. 1+≤ ii σσ for i = 1, …, �.
Si3N4 (SN I) exhibits moderately elongated Si3N4 grains with the aspect ratio of approximately 3.
The Si3N4 (SN II) has a bimodal grain size distribution with large grains up to 10 µm in length, and small ones, i.e. <1 µm in diameter.The SiC microstructure consists of fine submicron-sized equiaxed SiC grains with a low aspect ratio.
Additionally, all materials contain an inter-granular phase in a form of very thin grain boundary films as well as in a form of triple points.

The top plate is mainly mudstone with excellent sealing performance (Table 1), the lithology of the bottom plate is fine grained and coarse fragment rocks are accompanied with.
Table 1 Statistical table of lithology facies of top and bottom coal beds plate in key exploratory wells in Turpan-Hami Basin Well number Xishanyao Formation Badaowan Formation Top surface of coal Thickness Top plate lithology Bottom plate lithology Top surface of coal Thickness Top plate lithology Bottom plate lithology Aishi 1 / / / / 1069 26 20m mudstone 27m glutenite Ai 1 450 24 50m mudstone 5m mudstone 833 10 6m carbonaceous mudstone 5m mudstone Nandan 2 1814.0 2.0 Sandy conglomerate Fine-grained sandstone 2322.0 3.0 Argillaceous sandstone Fine-grained sandstone Yue 1 1656 24 11m mudstone 17m medium grained sandstone / / / / Fang 1 2327.5 6.5 28m fine-grained sandstone 6m siltstone 2796.0 3 5m Carbonaceous mudstone 6m fine-grained sandstone Mi 1 1562.5 17 3m mudstone 8m siltstone / / / / Sanpu 1 2123 9.5 5m silty mudstone 2m silty mudstone 2194.0 4.0 9m Muddy Siltstone 39m Muddy Siltstone Hashi 1 1082.8 5.2 3m Carbonaceous mudstone 1m mudstone

They also suggested that a slight change in Ce concentration produce a transformation from a nucleation and growth process to a grain growth process.
In an isothermal scan, a thermal signal that exhibited a monotonical decrease with time has been characteristic of a grain growth process by Chen and Spaepen in a sputtered AlMn alloy [9, 10].
The isothermal scan of Al83Ni10Ce5Si2 glass provides a monotonical decrease signal indicating a grain growth process without the corresponding nucleation process.
Then, a grain growth process of fcc-Al take place to form a microstructure of nanometer-sized Al crystals embedded in the amorphous matrix, as shown in Fig 3 (b) and (c).
Acknowledgement This work has been supported by the Science Foundationof Hebei (project Number. 09395113D).

It is featured by tough and tensile quality with fine grain, being a little acidic.
The grain of the windward wood is thin.
In contrast, the grain of the leeward wood is thick.
Arrange the shape according to the direction of wood grain in the gradual carving.
The carving organizes a number of figures horizontally according to the length of the beam.

At ambient temperature, these alloys deform by slip in the base plane, which affords a limited number of slip systems.
It can be seen that strain increasing causes the grain refinement.
The grains are elongated and oriented along the direction of drawing.
Some grains contain twins distortion and determination affects the increase of hardness and a loss of plasticity of the material.
The crystallographic orientation assigned to each point represents the size and distribution of individual grains.

In tool manufacturing different diamond grain sizes are used in grinding.
The calculated value represents the average chip thickness at the grains of the grinding wheel.
The chip thickness describes the mechanical load in the material removal and is predominantly induced by the diamond grain size [10].
Simultaneously the thermal effect in the contact zone between the diamond grains and the workpiece surface is intensified.
(AiF) with project number 12600N.

To improve mechanical properties of ceramic materials, a large number of research results were reported such as fiber reinforced composites [1] and laminated structures[2].
But fabrication of intra-type nano-structure is very difficult because the dispersed particles segregate to grain-boundaries of matrix materials.
And we added 10 mass% of α-alumina (AKP-53, Sumitomo Chemical, Japan, average grain size 300 nm) as a seed.
And grain size of seeded nanocomposites is smaller than that of non-seed nanocomposites.
In this case, the dislocations in both specimens were removed through grain boundaries.

Fig. 7 shows the subsurface crack depth of quartz glass ground by grinding wheels with the abrasive grain of #1500 and #2000.
According to the indentation fracture mechanics, the grinding process can be seen as a large number of sharp indenters scratching on the quartz glass surface.
However, when the cutting depth of abrasive grain is less than the critical cutting depth, the material removal will be in the type of ductile mode.
As the grains height on the grinding wheel varying in different positions, crack depth will change on various places of the surface.
Conclusion This work investigated the surface layer quality of quartz glass ground using vitrified bond diamond grinding wheels with abrasive grains of #1500 and #2000.

However, there have been very few studies on the effect of grain size reduction by means of the ECAP process on the resistance to pitting corrosion of Al alloys with and without anodization [4-6].
The initial grain sizes of Al and Al-Mg alloy prior to ECAP were 30-50 µm.
Their average grain sizes after the ECAP process were confirmed by TEM observation to be respectively 0.5-1.0 µm (Al) and 0.2-0.5 µm (Al-Mg).
The ECAP process markedly increases the number of grain boundaries and the dislocation density in Al.
The oxidation rate of Al appears to increase as a result of the increase in grain boundary and dislocation density caused by ECAP.

It was found that the thin innermost, fine grained layer consists of sulphides and oxides of Mn, Cr and Fe, the intermediate layer is built mainly of MnCr2O4 spinel, while MnO is the main component of the outer layer.
Tracer diffusion coefficients of 51Cr, 54Mn and 59Fe in studied Cr-Mn steels at 1173 K The sample method DT (Cr) [cm2s-1] DT (Mn) [cm2s-1] DT (Fe) [cm2s-1] * 1 (11.0 ± 2.0)·10 -12 (16.4 ± 1.4)·10-12 (12.0 ± 2.0)·10 -12 Cr13Mn18SiCa * 2 (17.0 ± 3.5)·10 -12 (16.6 ± 1.6)·10-12 (10.5 ± 1.0)·10 -12 1 (6.7 ± 2.2)·10-12 (11.8 ± 1.2)·10-12 (7.6 ± 0.8)·10 -12 Cr17Mn17 2 (6.8 ± 0.4)·10-12 (9.6 ± 0.7)·10 -12 (6.7 ± 0.4)·10 -12 1 (2.0 ± 0.5)·10-12 (3.5 ± 1.1)·10 -12 (1.7 ± 0.3)·10 -12 Cr15Mn19 2 (2.7 ± 0.3)·10-12 (3.6 ± 0.5)·10 -12 (1.9 ± 0.5)·10 -12 Legend: * 1- differential method, * 2-integral method The experimental profiles obtained at 1073 K indicate that the high diffusivity paths, like grain boundary diffusion, dominate and consequently other methods of analysis should be applied.
In type-A kinetics, each diffusing atom has migrated sufficiently far to have entered, migrated in, and left a number of grain boundaries or dislocations before the end of the diffusion anneal.
Then the effective diffusion coefficient (Deff) can be evaluated according to the equation: gb eff fDDD += * (4) were: D* - bulk diffusion coefficient, D gb - grain boundary diffusion coefficient, f - the fraction of atomic sites that are at grain boundaries or dislocations.
Gust: Fundamentals of Grain Boundary and Interphase Boundary Diffusion (Ziegler Press, Stuttgart 1988), pp. 20, 78 [11] J.