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In condition of ensuring single grain sampling, fixed the structure parameters of sampling rollers for South grains and North-east grains.
So to improve the mechanization level of grains drying is an important guarantee for grains harvest[1,2].
Grains size Varieties Southern grains Northeast grains Sample number 300 300 Average of lenghth [mm] 10.17 7.07 Standard deviation of length [mm] 0.08 0.02 Coefficient of variation for Length [%] 1.88 0.71 Average of width [mm] 2.1 3.41 Standard deviation of width [mm] 0.03 0.03 Coefficient of variation for width [%] 3.38 2.07 Average of height [mm] 1.78 2.34 Standard deviation of height [mm] 0.03 0.03 Coefficient of variation for height [%] 5.2 3.04 Learn from Table 1: (1) The geometrical size of different grains are different.
(3) Sampling single grain rate is between 92%～100%, which is a well single grain rate.
South grains is more tiny and prolate, meanwhile North-east grain is more round and full

Silicon carbide with diffierent granularity and three grain composition was used as raw material.
Table 1 Silicon carbide grain composition in the experiment Number 1.0-0.5mm (wt%) 0.5-0.1mm (wt%) ＜45μm (wt%) ＜5μm (wt%) 1 45 15 20 20 2 50 17 20 13 3 54 13 20 13 Sample Preparation.
Doped with 6% (in mass, similarly hereinafter) additive (PVA, 2% concentration) into the mixed material, after 6 hours, the mixture was molded to 56 mm×10 mm×10 mm specimens at pressure of 100 MPa by a hydraulic press (NYL-300), finally the specimens were sintered 1400 °C, 1450 °C and 1500 °C for 3h, were respectively coded as A, B and C, such as A-1, B-1 and C-1 (taking grain composition Number 1 in Table 1 for instance).
Results and Discussion Effects of grain composition on properties of silicon carbide material.
Sample A-2 has good densification, it has the best grain composition.

Thus the results conclude that the mechanical properties of Al-Si alloys in general are controlled by a number of principal microstructural features.
A fine grain size is desirable, leading to improvement of mechanical properties. 1.
With the inoculation of the grain refiners and the modifier into the Al-Si alloy melt, heterogeneous nucleation sites are created for solid α-Al resulting in finer grain size.
The microstructure is fully equiaxed and no columnar grain is observed.
It is observed that the grain structure has become finer after inoculating the LM6 base alloy with grain refiner 0.2%wt Al-5Ti-1B.

In all cases mesoscopic grain/interphase boundary sliding (~ grain diameter or more) is suggested to be the rate controlling mechanism [1–3].
A high–angle grain boundary is divided into a number of atomic scale ensembles that surround free volume sites present at discrete locations characteristic of the boundary.
The grain shape is assumed to be rhombic dodecahedron.
The average grain size is L.
The grain sizes in all but one system are in the sub-micron range.

A number of studies have shown changes in the bead microstructure through the use of shaped laser beams [4,5].
These distributions have been developed following a number of investigations (6-10).
The grain size is large with grains extending from the surface of the bead to the interface.
Although the grains in the Gaussian deposit have the highest aspect ratio it also has the smallest average grain size, Fig 4(b).
The grain size in the HAZs are shown in Fig.4.

Because of poor ductility in Mg alloys owing to their limited number of slip systems at ambient temperatures, most SPDs of these alloys are carried out at elevated temperatures.
The rate of grain refinement by MDF is accelerated when the initial grain is finer [7].
This is presumably attributed to the role of grain boundaries in grain refinement.
The former contributes dominantly to grain fragmentation when the grain is coarse, and the latter, when the grain is fine [9].
The grain size was larger than those of MDFed Mg alloys having an initial finer grain.

This program, with high speed and simple algorithm for random tessellation has the ability to change the level of statistical parameters such as number, mean, variance of the area of the grain.
In a random tessellation, the number of cells, the number of their segments and their shapes are all random.
This program, with high speed running and simple algorithm for random tessellation has the ability to change the level of statistical parameters such as number, mean, variance of the grains area.
Number of alpha phase grain (brighter phase in actual picture) and beta phase grain (dark phase in the actual picture), the percentage of alpha phase and the distribution area of alpha phase are the image processing component outputs.
(b) Processed image of microstructure In Fig. 4 total number of grain are 122 and area fraction of alpha phase is 0.4.

The grain boundary sliding and the formation of slipped bands and cavitations during biaxial tensile deformation were examined in fine grained Al-Mg alloy.
It was found that at the same equivalent strain conditions, the number of cavities under biaxial tension is significantly greater than that under uniaxial tension.
Voids and grain boundary sliding at the grain boundaries normal to the tensile direction as well as fibrous structures can be confirmed.
Dynamic recrystallization and grain growth are considered to contribute to the above, since the amounts of rotation of crystal grains and grain boundary sliding are large under uniaxial stress.
The scratches are bent in undulations at grain boundaries, but straight inside grains, and their inclinations are varied at grain boundaries.

Rebar rolling presents differences relative to flat rolling that can affect the role of Nb, such as the application of higher number of rolling passes, higher strain rates, lower interpass times, and, consequently, enhanced adiabatic heating.
Increasing the number of passes can contribute to austenite grain refinement.
For instance, the larger number of passes and the lower interpass times can help to refine the austenite microstructure, leading in some cases to the activation of dynamic recrystallization and to the development of very fine equiaxed austenite microstructures after deformation [[] B.
(a) 0.029Nb steel, average grain size (b) 0.015Nb steel, average grain size (c) 0.029Nb steel, Dc20 (d) 0.015Nb steel, Dc20 Fig. 3.
Regarding the 0.015Nb steel, at 1150ºC reheating condition, the precipitation behavior was very heterogeneous: large areas of the replicas were free of precipitates while a significant number of them were found in others.

The liquid metal flow speed between different grains was affected by the relative position and morphology between different grains, and also affected by the initial inflow speed of the liquid metal.
The number of grains takes any number smaller than the maximum nucleation number, the maximum nucleation number can be calculated using the formula for nucleation density [12], and the expression is as equation (13), （13） Where ∆Tmax is maximum nucleation undercooling, ∆Tσ is standard deviation undercooling, nmax is the maximum nucleation density.
Numerical Calculation Correspond to the x and y axis (the horizontal direction is x) in coordinate system, the computational grid number of phase field and solute field both are 1200×1200, the grid size is 1 × 10-8m (Δx = 1 × 10-8m ), set the initial nucleus as the ball with the grids number radius R=10.
In Fig.4, the large velocity absolute value area is close to the solid crystal region, and the corresponding abscissa grid number is between 700 and 800.
When the horizontal grid number is above 1100, the absolute value of velocity is gradually reduced to a value close to the initial value.