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Electron backscatter diffraction (EBSD) was used for characterizing the preferred orientation, grain size distribution, and grain boundary character distribution.
Due to a number of data obtained from EBSD analysis, it is impossible to present all of results and therefore Fig.1 shows, for instance, the orientation image map, the inverse pole figure and the grain size distribution under the current density 0.5A/cm2 and the frequency 340Hz.
Using OIM analysis software, the average area grain size ν is determined by the following: ∑∑ == = � i i � i ii AA 1 1 νν (1) where iA is the area of grain i , and iν is the grain size of grain i .
If the average grain size and twin fraction are displayed in a plot in Fig. 2, it was observed that the grain size increases as the twin fraction increases.
In the case of the grain size > 1 µm, however, the twin fraction decreases, as the grain size increases.

For the calculations presented below, the initial deformed state was described by a two dimensional set of grains, similar to an EBSD map, containing approximately 2000 grains.
The grain structure is represented by vertices with positions       = k k k y x r r , where N,...,1k = (N is the number of vertices in the structure).
Each (sub) grain has its orientation On and the stored energy value En.
The initial positions of vertices in grains are the corners of a Voronoi structure.
During recrystallization process, the grain structure undergoes topological changes.

The working principle involves the receptor function played by the surface of each oxide grain and the transducer function played by each grain boundary.
Firstly, we should mill the original monoclinic zirconia prepared before in planetary ball mill for 12 hours to make its original grain size under 1 μm.
Made a number of circular sheet embryos with the diameter of 20mm,a thickness of 5mm and a number of test bar with length of 60 mm, width of 4 mm, height of 3 mm.
From Figure 1, the grains of 5YSZ(yttria untreated) are smaller and more uniform than 5YSZ(yttria 1300°C); On the contrary, the grains of 8YSZ(yttria 1300°C) are smaller and more uniform than 8YSZ(yttria untreated), and the grains of 8YSZ(yttria untreated) are not in the same plane, the performance of 8YSZ(yttria untreated) is bad.

Figure 3 shows the surface roughness as a function of the number of slurry pass for various size grains.
It is found that the surface roughness decreases remarkably in the early stage of low number of slurry pass less than 40, and then the decreasing rate of roughness becomes gradually gentle as increasing number of slurry pass.
It is also found that the decreasing rate of the surface roughness for grains of 57Ǵm in size is higher than those of the other grains of 57Ǵm in size is higher than those of fine grains of 5.5 and 20Ǵm in size.
The decreasing rate of roughness in the early stage in the polishing with 57Ǵm grains is much steeper than those in the polishing with 5.5 and 20Ǵm grains.
Figures 4 and 5 show the variation of the surface roughness with the number of slurry pass for various grain concentrations and slurry injection pressure , respectively.

According to rough statistics, the number of cooling holes in single advanced aero-engine has reached hundreds of thousands.
The crystalline grain size of 2 # sample is more uniform and 33.32μmin diameter on average, while other crystalline grain size between 40.36μmand74.83μm.
On the contrary, when the addition amount of La3+ was over high, the probability of grain nucleus growth was increased, which lead to a coarse-grain and a loose structure of coating layer.
Fig.7 Affection diagram of grain size, micro-hardness and electrode loss rate number of tube electrode electrode loss ratθ（%） average grain size（μm） microhardness（HV） measurement (HV) value Fig.8shows the surface micro-morphology of 1#copper and 5# electrode after EDM machining.
The material micro-structure mainly included three parts: the grain size, the uniformity degree of the grain distribution and grain orientation.

On the periphery of austenitic grains martensitic layer is observed.
On the periphery of austenitic grains a martensitic layer is formed.
Metallographic study of areas that have experienced repeated heating and formed not only on the surface but also throughout the depth of the zone of thermal influence, revealed a number of features.
The minimum values of the reflection angle correspond to the increased amount of austenite (Fig. 2 c) that is associated with the greatest number as part of this phase of carbon.
On the periphery of austenitic grains there is a martensitic layer. 3.

Grains reveal higher hardness, strength and regularity with comparison to Al2O3 grains (corundum).
Fig. 1 Wear of abrasive grains, a) Al2O3 grain prior to use, b) the grain Al2O3 after use, c) the grain SG prior to use, d) SG grain after application Abrasive grain is so tenacious that in order to prevent the occurrence of excessive forces during grinding it is mixed with conventionally fused corundum grains at the grinding wheel production.
Fig. 2 TG 2 abrasive grains [6] The further SG grains development mainly focuses on the production of new forms of grains.
Applying the load to grains a conchoidal fracture occurs and thereby increasing of number and sharpness of the cutting edges.
The grain has self-sharpening properties of ceramics grains but with a slower course [5].

The RS P/M alloy was consisted of fine grain size Mg (100 -150 nm), and a long period stacking ordered (LPSO) phase which is dispersed in Mg grains.
The high strain rate superplasticity is believed to be due primarily to grain boundary sliding of fine Mg grains.
Superplasticity is desirable deformation mechanism for Mg based alloy due to the limited number of slip systems.
From TEM observation of the Mg phase in the fractured specimen, Mg grains show fine grain (about 1μm) and seems equiaxed, therefore, it is considered that grain boundary sliding of Mg grains is dominant deformation mechanism of the Mg96Zn2Y2 extruded alloy at high temperature range.
Although the LPSO- and Mg3Zn3Y2- phases showed relatively large grain size, the Mg grains showed a mean grain size of 450 nm. 2) The Mg96Zn2Y2 extruded alloy exhibited superplasticity at temperatures of 623 K and 723 K.

The experimental recrystallized texture presents a complete γ fiber, with Journal Title and Volume Number (to be inserted by the publisher) 3 a reinforcement of the {111}<110> comparatively to the {111}<112>, stronger than the modelling one.
A relatively good agreement in terms of grain morphology and grain size is obtained.
However, the Journal Title and Volume Number (to be inserted by the publisher) 5 recrystallized texture is not well reproduced.
At the TEM scale [13], the nucleation is observed near the grain boundaries as well as inside grains.
The nuclei grow into the "parent" grains without consuming the neighbouring grains.

The corrosion of these refractories were investigated in a number of studies [6-9].
Backscattered electron imaging (BSE) was primarily used for SEM examination of polished specimens due to the ability to separate different phases based on the atomic number contrasts [4].
Exsolved spinel was widely observed within the periclase grains but the grain boundary phases of periclase grains will not be reported here for the sake of brevity.
Selected spots along a line extending from the center area to the rim are numbered 1-4 in Figure 2a.
M: magnesia grain, Cr:chromite grain.