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Six samples were cut from the center axial position with the angle between every two samples is about 15 ° as shown in Figure 3 and numbered as S1~S6.
Table 1 Surface indices and misorientation angles α between surface indices and {110}, misorientation angles β between surface indices and {112} for the six samples Sample Number Angle range Surface indices α β S1 1-15° 616 7° 25° S2 16-30° 415 11° 19° S3 31-45° 214 22° 11° S4 46-60° 235 23° 7° S5 61-75° 415 11° 19° S6 76-90° 123 19° 11° Small grains on the surface of the single crystal tungsten coating after working.
The average grain size of these small grains is about 200μm.
According to this, it could be found that the grain boundaries between the small grains and single crystal tungsten coating are large angle grain boundaries.
Further research work is needed to find the reason for emergence of small grains.

Since the 1980s of the last century, many scholars have carried out a large number of simulation studies on complete structure of single crystal materials in nano cutting process.
In these cutting model, a variety of structural factors on the effect of the process are taken into consideration, such as, grain interior presence of point defects (vacancies and inclusions), line defects (dislocations), different grain crystal orientation (small angle grain boundaries).
Fig. 1 Material atoms divided into four parts A, B, C, D from right to left in turn, and in the crystal Fig. 1 The model of polysilicon nano cutting grains A existed voids and inclusions typical point defects; Grain B and grain C constituted a typical small-angle grain sector, and the crystal orientation angle of grain C and grain D is 5 °, and the crystal orientation angle of grain B and grain A is minus 5 °, and the junction of grain B and grain C is the transition structure of the grain boundary structure, in which there is obvious inclusions phenomenon, and obvious dislocation structure and the internal can be seen between grain B and grain C; Grain D is more complete grain.
When the knife cut into the small-angle grain boundaries, the junction area of the grain A and B, a large amount of atoms accumulate around grain boundary and the cutting force correspondingly have a significant change, much larger in area B than in A.
When the knife cut into the transition area between grains B and C at the grain boundaries, the inter-atomic forces become more complex, cutting force fluctuations also slightly enhanced.

Fig.5 shows the grain size under different C2H2 flow rate.
Because of the fixed arc current and bias voltage, the number of nickel ad-atoms is constant in a unit time.
The Mean Grain Separation.
Considering the microstructure of the film, the mean grain separation between the mental grains equals to the thickness of the amorphous carbon.
The grain size is in the range of 7.9-11.6 nm.

The corrosion resistance decrease is due to grain growth.
The alloys have been fully recrystallized; By comparing the conventional solution treatment, the grain size after the enhanced solution treatment grew larger, the volume and size of the second phases along grain boundaries decrease obviously and the second phases in grains are mostly dissolved in the matrix.
It is visible that prolong solution time and improve the solution temperature is more conducive to dissolve the second phases, especially the coarse second phases along the grain boundaries.
Enhanced solution treatment significantly reduces the number of undissolved coarse second phase, weakens the early fracture caused by coarse phases on grain boundaries, it can also increase supersaturation, increase the driving force of phase transition in the aging process, decrease the critical nucleation size, increase the nucleation rate, and facilitate the formation fine dispersed precipitates what enhance the strengthening effect.
Intergranular corrosion is mainly refers to the corrosion occurred near the grain boundaries or along the grain boundary, exfoliation corrosion is mainly refers to lamellar stripping parallel to the substrate surface, Both of them are related to grain boundaries [11], therefore, corrosion resistance of the alloy is mainly determined by the size and distrubution of precipitates on grain boundaries.

Grain crushing is a common phenomenon in these constructions.
Grain crushing is an irreversible physical process.
The broken rate b0m are calculated from the final fracture number ni..
The equivalent grain size dm can then obtained using the broken rate.
However, due to the number of this kind of cluster is limited in the numerical model, the difference is not huge.

A number of low voltage varistor materials reported in the literature such as based on WO3, TiO2, etc [3-5].
The grain sizes were calculated by microstructure linear analysis.
According to the boundary barrier model, the breakdown voltage , Eb, for a varistor is determind by the mean number of barriers n in series multiplied by vb, that is [15] : (2) where vb is the voltage barrier at a grain boundary, which is almost a constant for different samples.
All the defects form a double barrier between the WO3 grains.
Doping La2O3 in WO3 ceramics can promote the grain growth.

The nanofibers are smooth and uniform throughout the entire length and the grain is growing as calcination temperature increases.
The collection time during electrospinning was controlled precisely to obtain a suitable (but not excessive) number of aligned nanowires on the substrate.
The grain size increases with the increasing of sintering temperature according to the peak width, as well as the crystallinity.
While the temperature reaching 1000°C, the grain growth so fast that the agglomeration appeared and the fiber structure collapsed.
For the nanofibers annealed that annealed under 800°C, the nanofibers are made of many samll grains.

PS represents a suitable material for diamond growth due to its large number of nucleation sites and surface area, becoming an excellent material for porous electrodes.
Since its discovery, more than six decades ago, a large number of investigations have been undertaken revealing that PS has extremely rich morphological features [1].
PS has been used as substrate to diamond films growth, in order to increase the number of diamond nucleation sites, improving the crystalline structure of the films [6].
The (111) peak widening, observed in both spectra, is related to the NCD grain size.
When inert gas diluent is used, NCD seems to form in H-poorly environment that leads to an enhanced mechanism for secondary nucleation, contributing to the formation of lower grains [19].

As observed in Fig. 5a and Fig. 5c, elongated grains with serrations develop on the grain boundaries, where DRX grains can be easily distinguished.
In addition, as shown in Fig.5c, more fine DRX grains nucleate on grain boundaries, where there are still a number of elongated grains in the deformed microstructures.
In Fig. 5d, the boundaries of the elongated grains are nearly straight and on the boundaries no recrystallized grains were observed.
The grains are elongated merely and grain boundaries are irregular, which indicates the typical dynamic recovery feature [10].
Whereas, there is sufficient time for storage energy and nucleate for DRX grains at low strain rate, and plenty of recrystallized grains are formed along the grain boundaries.

material B 0 2% 5% 7.8% 7.8% 7.8% Table 2 Comparison Experiment number Comparison Experimental Program 8# Magnetic components are controlled by sample 6.
The magnet cross-section SEM analysis show that the crystals are relatively regular laminated structure; grain size is uniform; grain interface is clear; the crystal structure is tightly packed; the average grain diameter is 1.67μm and porosity magnet is 0.56%.
It shows that the crystal is a sheet structure and there is small amount of abnormal grain, besides the grain boundary is not clear.
After the formation of the magnetic field, the preferred orientation grains have faster growth rate than the surrounding non-orientation grains and the fast growth orientation grains tend to merge the non-orientation grains in the process of the sintering of the samples parallel to the easy magnetization axis (C axis). [5] Soft magnetic ferrite components (CoFe2O4) are easy orientation particles.
So adding soft magnetic ferrite components increase the number of easy orientation grains and the tendency of merging non-orientation grains, thereby improving material remanence Br; 0n the other hand, due to the presence of magnetic anisotropy, the magnetic moment of single domain particles tend to orientate along the easy magnetization direction, which seems to exist an effective magnetic field in easy magnetization direction, namely, all the magnetic crystal anisotropy field.