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The alloys with the coarse-grained and microcrystalline structures were used in a heat-strengthened condition.
Another aspect is obvious decrease in heat-resistant characteristics while decrease in grain size.
Three types of microstructure were produced by various processing: coarse-grained lamellar (CG - grain size 400 µm), microcrystalline (MC - 10 µm) and SMC (0.4 µm) structures (Fig. 1).
Optimum annealing conditions to attain the maximum structure improvement without grain growth were determined from pilot experiments.
Materials with SMC structure cannot be heat strengthened without grain growth.

The grains were substantially refined, the preferred orientation of (200) face weakened and the microhardness significantly increased.
Further more, the particles can refine the grains, polish the surface of deposit, and reduce the degree of roughness and irregularity.
The crystal grain size (D) evaluated from the broadening of the (200) peak according to Scherrer's formula.
Here n=3 is the number of the diffraction peak.
According to Reddy's postulate [9], differently oriented grains of polycrystalline metallic deposits have different growth rates.

The organizational structure is analyzed with metallographic microscope, and the results show that dynamic recrystallization is occurred, the grain size is obviously refined, and the mechanical property of the material is improved in hot rolling process.
Rolling process (1) When resistance furnace raised to a predetermined temperature blank is put into the oven to heat, and preheat roller to about 350˚C; (2) When the blank is heated to 380˚C, is fed into the Y-type three-roller mill which roller diameter 500mm, the rolling speed of 40 r/min, the number of the rack 4 (using a motor driven collective) Motor power 900kw, using the cylinder oil + graphite as a lubricant
(2) Microstructure （a）cast state （b）rolling state Fig.7 Metallographic of AZ31 alloy Figure 7 (a) shows AZ31 magnesium alloy billets uniformity treated, it can be seen that rod grains relatively coarse, the grain size about 200μm; Figure 7 (b) shows microstructure of rod surface after rolling deformation, rod grain significantly refined, grain size about 10μm.
Because of the small grains, ductility and toughness have been strengthened, indicating hot rolling improves mechanical properties of materials [12].
(2) The organization observed of AZ31 alloy rods show that after hot rolled dynamic recrystallization occurs, grain size has been significantly refined, with an average grain size of about 10μm

Therefore, the film is mainly constituted by microcrystalline Silicon grains embedded in a-SiC:H tissue.
The calculated grain size of Si (220) phase is 23 nm.
The grain size of Si (220) phase is 33 nm for the silicon carbide film with gold coating.
It should also be noticed that the first absorption peak shifts to the higher wave number, and its shape changes from Gaussian type to Lorenz type.
The big bright crystallites seen in the micrograph can be ascribed to the gold grain or silicon gold alloy grains.

At first, EDM machinability was compared between two kinds of PCDs (10µm grain size), i.e. standard PCD (S-PCD) and electrically conductive PCD (EC-PCD (which was made of boron doped diamond particles).
Further experiments were conducted with EC-PCD of different grain sizes such as 2µm and 5µm.
As a result, the smaller the grain size of EC-PCD the higher the machining efficiency was.
To be precise, 3 kinds of EC-PCD with different grain sizes of 2, 5 and 10µm were examined.
Each PCD was cut by EDM into a circular plate of f3.2mm, which was then brazed to a steel bar to be used as a shank Fig.2 Experimental setup of R-shape forming PCD Hemispherical hole: R1.5mm Copper electrode Fig.1 Schemof R-shape forming by EDM Table 1 Experimental device and conditions for R-shape forming EDM machine Die sinking EDM machine (AQ35L，Sodick) PCD workpiece Standard PCD (S-PCD, Diamond grain size：10µm) Electrically conductive PCD (EC-PCD, Diamond grain size：2,5,10µm) Copper electrode Hemispherical hole: R1.5mm EDM condition Rough EDM condition: PCD[-], ui=90V, SV=55V, iP=9A, te/to=5/10µs Finish EDM condition: PCD[+], ui=90V, SV=55V, iP=3A, te/to=0.5/5µs Tool rotation number: N=100min-1 Working fluid Oil (VITOL 2, Sodick) Fig.3 Comparison of machining efficiency in the 1st R-shape forming Machining time t [min] S-PCD010 EC-PCD010 EC-PCD005 EC-PCD002 EDM Machine and Machining Conditions.

Translucency, as the key requirement, is controlled by means of grain size.
The latest development of PCA with regard to the control of the grain size during sintering occurs in two directions: 1) enhancement of the abnormal grain growth to convert PCA to single crystalline sapphire [5-7] 2) suppression of the grain growth and achieving submicron-grained microstructure during sintering of nano-size alumina powder [8-10].
However, this grain is adjacent to intergranularly broken grains and the directions of intragranular crack propagation vary from one grain to another.
Besides conventional inter- and transgranular (conchoidal) fracture, cleavage - faceted fracture along the special cleavage planes with weaker bonding - occured in the limited number of the individual grains (see Fig. 6).
High value of m and the narrow scatter of strength data suggests that fracture may originates only from small anomalies within the microstructure, most probably the grains at the upper end of the grain size distribution.

With spin-coating numbers of 5, the (001) / (100) peak was asymmetric.
In this study, the nucleation of the interface between the layers formed randomly oriented crystals when increasing the spin-coating number from the critical number.
At x=0.2, the SEM micrograph showed the grain uniformly distributed and the small pore structure appeared in the surface.
When increasing barium, the film surface appeared porous, including different grains, and the size was un-uniform.
Wang, Grain size effect on the phase transitions in oriented PbTiO3 thin films deposited by the sol-gel method on (111) Pt/Si, Mater.

The hysteresis loss is sensitive to structure and decreased by the following methods: increasing grain size, lowering the level of interstitial impurities such as carbon, nitrogen, oxygen and sulphur, reducing the number of non-metallic inclusions or precipitates, avoiding the introduction of stress, and developing favorable crystallographic textures.
It can be considered that small grain size in the center layer results from low mobility of grain boundary.
The grain size effect on core loss can be negligible because the grain sizes of final products are similar.
Grains with {111} textures tend to nucleate at the grain boundaries.
Therefore, the grain size effect on core loss can be negligible because the grain sizes of final products are similar.

Furthermore, the simpler the model (small number of parameters) used in the simulation, the more relevant the measurement (minimum error).
Grain boundary segregation.
Moving grain boundaries.
If we consider that not all the grains are growing, the fraction of growing grains fgr can be a fourth parameter.
However, if 10% of the grains are growing (fgr = 0.1), the grain growth effect on the profile is not negligible anymore.

In order to promote its application, its construction method is researched by to adopt the technology of "high in-situ construction" and in combination with the construction a grain storehouse.
The general situation of a grain storehouse The grain storehouse’s span is 24 m, the warehouse’s length is 57 m, the installation elevation of the roof’s lower boom plate is 7.8 m, the wall thickness is 490 mm.
All the transverse pole needs to support the structure tightly, make the platform forming a whole with the grain storehouse structure. 2.
Embed bolt diameter, the number and anchorage depth must be calculated, and should be considered in the construction of produce negative factors.
References [1] Kechao Zhao, Lei Xie: Advanced Materials Research Vols. 250-253 (2011), p 1883-1888 [2] Zhenqing Wang, in Chinese: 《Granary architecture and structure》，China Business Press，(2006) [3] Xinyou Wu, in Chinese: Construction Technical , (2008) [4] Yinlai Liu, in Chinese: Grain Distribution Technology, (2009) [5] Bing Luo, Zhengxing Guo, in Chinese: Special Structure, (2008)