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With the number of a-Si3N4 grains increased, the weight loss decreased gradually.
With the number of a-Si3N4 grains increased, the linear shrinkage gradually decreased.
Therefore, as the number of a-Si3N4 grains increased, the linear shrinkage decreased gradually.
Although the size of the β-Si3N4 grains was relatively small, the number of the rod-like β-Si3N4 grains with a high aspect ratio was small.
Therefore, the distribution of β-Si3N4 grains size was relatively even, and the number of coarsened β-Si3N4 grains was relatively small.

The TBRVE consists of a certain number of grains and orientations of the polycrystal, which conveniently represents the global texture and can capture the mechanical response of the material including the BE under cyclic loading.
It is a small volume element which contains a sufficient number of grains to model the global response of the macro-scale specimen.
The EBSD data obtained on the AA7075 specimen is imported to the MTEX toolbox [26] where the ODF is generated, and then crystallographic orientations are obtained by discretising this ODF with the grain number in the RVE as the control parameter.
Before carrying out the simulations, convergence studies in terms of grain number, grain orientation, mesh density and tessellation were conducted to obtain the appropriate RVE.
The model consists of a total number of 51840 brick elements (C3D8R), and the grain tessellations at the edges have been created to be repeatable in each direction.

In order to locate and segment the image of grain bags in the granary reserves, and making full use of the spatial location information of grain bags, a threshold method is proposed base on two-dimensional Fisher criterion.
It is of great practical significance for upgrading the supervision level of grain management.
(3) where, is the integer function, let K that is usually an odd number denote the neighborhood width of pixel (x, y).
In the actual scene of grain bags reserves, the grain bags had the characteristics of relatively consistent, while the gray value of each bag region are concentrated and well-distributed.
In terms of the segmentation results, the traditional 1D Fisher method can segment each grain bag region, but that approach had some segmentation error, caused loss of some grain bag regions.

First, the exponent of the inverse grain size is given by p = 2.
The alloy had an initial grain size of ~1.8 μm after annealing at 473 K for 1 h and was refined by ECAP processing for 8 passes to have a mean linear grain size of ~0.8 μm [8].
It should be noted that the tensile axis is vertical in the micrograph in Fig. 1(b) and the grains appearing white are the Zn-rich grains and the grains appearing dark are Al-rich grains.
The disk samples with a diameter of ~10 mm and a thickness of ~0.80 mm were processed under a pressure of 6.0 GPa at 1 rpm for total numbers of 4 and 5 turns in a constant rotational direction.
There is a reasonably homogeneous distribution of Zn and Al grains with an average linear intercept grain size of ~350 nm.

The increase in vibration accelerates the grain to fill the empty space between the grains.
In general, the soil grains are distinguished into: gravel, sand, silt and clay, which are commonly found in natural soil deposits in the form of mixed grains.
Amplitude is the maximum displacement, while the frequency is the number of vibrations per second.
During experiment the movement of sand grains recorded.
This was due to the greater frequency of vibration, the faster of grain movement to fill the empty space between the grains so that, the landslide field is wider.

For the films fired at 750�, the needle-shaped grains (a-axis grains) were very fine and pores were frequently observed.
In addition, the a-axis grains disappeared as the firing temperature was increased to 775�, suggesting that the grains mainly consisted of c-axis grains.
It then decreased drastically to 54 A/cm-width with increasing number of coatings.
The film thickness increased almost linearly with increasing number of coatings up to 5 times.
XRD patterns of the films with the number of coatings

The tensile strength, compressive strength and the elongation to failure of the fine-grained AZ31 are enhanced due to the reduction of grain size.
Reduction of the mean grain size is also expected to promote super-plastic deformation at higher strain rates and/or lower temperature than those conventionally used for large grain size materials.
The number of ECAP passes was six.
The structure is an equaled grains with a grain size of about 120µm.The sample subjected to six passes has a homogeneous, fine-grained microstructure with a grain size of about 8µm, as it can be seen in Fig. 1b.
A fine-grained Mg alloy AZ31 was obtained by ECAP.

Overall，the average ferrite grain sizes in the three tested rebar are fine, which have fine grained strengthened effect and are contribute to improve strength and plasticity.
Ferrite content /% Pearlite content /% Bainite content /% Ferrite grain size /um Ferrite grain grade /grade 1# 59.3 40.7 / 8.5 10.4 2# 49.1 26.8 24.1 8.6 10.6 3# 56.7 36.6 6.7 8.6 10.6 Table 3 Quantitative analysis results of microstructure and ferrite grain size for different microalloyed rebars.
According to the test results of precipitates, a large number of V(CN) and Nb (CN) precipitates with size of 5～30nm are formed and distributed on ferrite matrix, grain boundary and dislocation lines.
The cleavage fracture is composed of a large number of cleavage plane with the size being equivalent of the grain size.
Becauce when crack grow and propagate, it would go through a certain number of parallel cleavage plane with different orientation,which result in grain boundaries become obstacles to crack propagation, grain size effect crack propagation that is the cleavage plane size increases with grain size increasing and grain boundaries crossed by crack propagation is lesser, therefore, the crack easily propagate and propagation rate is also faster, which easily lead to cleavage brittleness fracture.

In grinding process, the point that enables to become a cutting-edge is only the highest point of grains.
Therefore, it is thought that the grains are maintained on the working surface, and then, the cutting-edge is generated on the top of those grains.
Since the grains are maintained, with progression of dressing, internal grains are exposed to the peripheral surface.
In other words, in case of less number of spark-out, since the grains damaged with dressing remain on the working surface, the shedding tends to occur with grinding.
This indicates that there is the critical value for the spark-out number in dressing.

Introduction Recently, industrial products have become increasingly smaller and a greater number of functions are required each year.
As a result, abrasive grains are concentrated and fixed around the tool tip.
The behavior of abrasive grains is then observed.
In order to obtain a more detailed understanding of the behavior of abrasive grains, the density of abrasive grains is less than in the case of the machining and the larger abrasive grains are used.
When the applied voltage is low, the electrophoretic force acting on abrasive grains is small, and abrasive grains cannot closely approach the micro tool (Fig. 6(b)).