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The results shown that glass ceramic phase is CaNb2O6, grain size is about 30 nm, The two-stage controlled heat treatment is beneficial to control of the number and size of grains, thus affecting the transparency of glass ceramic and luminescence properties.
Fig.3 shows grain morphology, size and crystal distribution of grain in the residual glass phase.
Changes of particle size and distribution are evident along with the extension of heat treatment temperature. heat treatment temperature on the morphology control of microcrystalline glass is very important, with the extension of heat treatment temperature, the grain number increase gradually.
Heat treatment temperature too short will result in fewer grains and inadequate growth.
Heat treatment temperature is too long, and leads to grain growth is too large, appear gathered themselves together, and results in uneven distribution of grain size, transmittance drop too fast.

Size and number of the void at the position of the 10mm diameter increased further than that at R part of the 4mm diameter.
Figure 4 shows the grain boundary maps obtained by EBSD analysis for each specimen at R part.
In comparison with both specimens, the grain size in the specimen made from the carbon fixed chip became slightly finer.
However, size and number of the void of the magnesium-carbon alloy were less than those of the A91D magnesium alloy.
Fig.6 Macro observation of fracture surface in various number of cycles for each specimen.

The equiaxed grain in 2# steel with higher coiling temperature is the more obvious.
From Fig. 1, it can be seen the microstructure obviously show pancake grain in 1# steel(seen in Fig. 1(a)), but the grains display equiaxed ones in 2# steel and 3# steel(seen in Fig. 1(b) and (c)) and equiaxed grain is the most obvious in 2# steel.
From Fig. 2, it can be seen the microstructures all compose of ferrite and cementite, but free cementite is dominant with minute numbers of line cementites in 1# steel, as shown in Fig. 2(a).
Large numbers of line cementites are observed in 2# steel and 3# steel, as shown in Fig. 2(b) and (c).
The equiaxed grain in the steel with high coiling temperature is the most obvious.

The mold surface was more smooth, and the number of stomata reduced .
At the same time , a cross-section was observed with the naked eye, the zinc alloy after solidification under pressure, compared to the material without pressure treatment, whose stoma number significantly reduced a lot.
At the same time, due to shorter crystallization time, which restricted the diffusion process of dendrites pressure made the growth of grains form smaller, thus played a grain refinement purposes.
The finer the grain is , the more plastic deformation can be spread in more grains, which will give more uniform plastic deformation, and the stress concentration is smaller; and the finer grain is ,the more interface it has, the more tortuous grain boundaries are; the more opportunities the grain interlocking have in the grains, the more difficult is conducive to the spread and development of cracks, at last ,the more tightening, the better strength and toughness will be.
Conclusion (1)In the casting process, the zinc alloy solidification with the nitrogen pressurized method could reduce shrinkage, its surface was more smooth, macroscopic density increased, with the number of stomata reducing

The weld nugget zone is composed of uniform fine equiaxed grains, while thermo mechanically affected zone is composed of slender coarse grains.
The average grain size is 9.5μm.
Then dislocations begin to move and grain grows unceasingly.
The average grain size is 13μm.
(3) Fine equiaxed grains were evenly distributed in the NZ area, while elongated coarse grains were observed in TMAZ area.

The code numbers for the variables used in the Table 4 were obtained from the following equations: （1） （2） （3） （4） Where, r is the number of replication of level (r=3), m is the number of level (m=3), n is the number of total test (n=9) and T is the sum of the testing results.
Al) is columnar grains around periphery and equiaxed grains in the center.
For 201 stainless steel, as shown in Fig.3, the typical microstructure of spot welded joint is the equiaxed grains around periphery and columnar crystals in nugget.
The HAZ has equiaxed grain structures shown in Fig.3 b.
When the welding current is over 6400A, because of the heat input increasing, larger columnar-dendritic grains can be observed.

Nearly pore-free microstructure (99.8%) and narrow grain size distribution (4-10 µm) with an average grain size of 7 µm was obtained for the sample sintered in the vacuum atmosphere, while both inner and inter pores with abnormal grain growth, wider grain size distribution (9-27 µm) with the average grain size of 12 µm were detected in air atmosphere.
This causes abnormal grain growth and trapping of pores inner and inter of the grain.
As the sintering temperature increases, the number of the pores decreases (Fig. 6 and 7) and the relative density and grain size increases (Fig. 8 and 9).
At temperature higher than 1590 ˚C, when the advanced stage of sintering occurs, the difference between the number of residual pores, relative densities, and grain sizes are observed for the specimens sintered under air and vacuum atmospheres.
However, both inner and inter pores with abnormal grain growth, wider grain size distribution (9-27 µm) with average grain size of 12 µm were detected in the air atmosphere sample.

Three different measurements with a different number of slices were carried out on one sample and the parameters are given in Table 1.
Measurement X (TD), [µm] Y (ND), [µm] Z (RD), [µm] Number of slices Volume, [µm³] 1 16 14 6.2 62 1388.8 2 15 10 6.5 65 975.0 3 15 10 2.7 27 405,0 Table1.
The grain shape of each individual grain from the examined volume was approximated with an ellipsoid.
After applying both cleaning methods, the total number of grains remaining from the three scans was 615.
(d) Quantitative description of the grains volume fraction as a function of the grains major axis with respect to the sample rolling direction.

The size of VC decreases and its number density increases by lowering transformation temperature, corresponding to the larger hardness increase.
Both specimens transformed at temperatures above 873K consist of pearlite and small amounts of proeutectoid ferrite along prior austenite grain boundaries and inside austenite grains.
Black region is untransformed austenite now transformed to martensite during quenching and bright region is grain boundary ferrite grains.
As shown in Fig. 4, a large part of ferrite grains hold near K-S relationship with one side of austenite grain and there is no ferrite grain holding near K-S relationship with both sides of austenite grains.
With lowering transformation temperature, dispersion of VC becomes finer in size and higher in number density

For example it was reported that for BaTiO3 the dielectric thickness will become less than 1um in a very near future and the number of layers could exceeds 1000 [2].
Much additional peaks were resolved when the grain size became large.
Especially, the peaks, corresponding to wave number ranging from 400 to 600 cm-1, became too broad to be observed.
Compared with photo frequency the FWHMA values are more sensitive to the grain size.
The corresponding critical grain size was about 22-33nm.