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However, much crystal grain scatters on the ground surface of sample C and D (Fig.C and Fig.D), the mean grain size is about 0.35µm, which approaches to the mean grain size of the samples.
Grain boundary cracking and crystal grain dropout are main removing method.
This is probably because there are many flaws introduced during the sintering procedure on the grain boundaries.
The flaking and brittle fracture is the main removing method for the samples with high flexural strength, and grain boundary cracking and crystal grain dropout are the key removing method for the samples with low flexural strength.
Large numbers of cracks would easily propagate and breach the ceramics which were subjected to enough high shear force such as grinding force.

The crack propagation is along prior-austenite grain boundaries and is affected by MnS inclusions.
Thus, the crack propagation is along the prior-austenite grain boundaries.
The ferrite, some of which has widmanstatten characteristic, proceeds along the prior-austenite grain boundaries.
Thus, prior-austenite grains in 0# position is coarsening.
MnS inclusions at cross-section of sample 45#, the number of which is less than that of sample 0#, are distributed approximately parallel to the surface as showing in Fig.7 (b).

The grain refinement, higher hardness and compressive residual stress are the three main reasons that enhance the fatigue capability of blade.
LSP has been proved that it is effective in improving material hardness and fatigue strength in a number of alloys [4-6].
Fig. 5(b) is the microstructure after LSP, the surface is grain refined and much smoother than the former.
The equation indicates that the smaller the grain granularity, the more intensity the material [10].
Furthermore, the grain refinement makes more grains to participate in deformation, and thus reduces the stress centralization that may lead to fatigue crack.

The x-ray diffraction analysis showed that the as-deposited films In2Se3 are amorphous in nature while the as-deposited film InSe and In3Se2 are nanocrystalline with grain size of 33nm and 55nm, respectively and the values of energy gap were Eg = 1.55eV for InSe and Eg=1.28eV for In3Se2.
Also, IGC has many other advantages over other nano-processing methods including: (i) the potentially very large number of pure metals, alloys and composite materials which can be deposited with grain sizes less than100 nm, (ii) few shape and size limitations, (iii) high production rates, (iv) low initial capital investment requirements and (v) most importantly, easily controllable processing parameters.
In order to determine the optical gap energy (Eg) from the optical absorption spectra, measured around the absorption edge, we have used Tauc equation [8]: (αhv)1/n = B (hv-Eg) (2) where B is a parameter depending on the transition probability and n is a number characterizing the transition process.
Transmission curve and energy gaps (a) a-In2Se3 and a-InSe (b) c-In3Se2 thin films deposited at room temperature We have measured the grain Crystallite size by using Scherrer’s formula: D = 0.94 λ /B cos θ (3) where B = FWHM of prominent peak, λ = wavelength of X-rays, θ = Bragg’s diffraction angle.
The X-Ray diffraction analysis showed that the as-deposited films In2Se3 are amorphous in nature while the as-deposited film InSe and In3Se2 are nanocrystalline with grain size 33nm and 55nm respectively and the values of energy gap are Eg=1.55eV for InSe and Eg=1.28eV for In3Se2 (Figs. 4 and 5).

The parallel with grain boundary diffusion.
There is an interesting parallel between dislocation and grain boundary diffusion.
Interstitials are as important in grain boundaries as vacancies.
In fact, such collective mechanisms dominate in most grain boundaries, which makes grain boundary diffusion similar to diffusion metallic glasses.
The goal of this step is to obtain a small enough number of dynamic atoms that permits long MD runs.

Scanning electron microscopy analysis of sandstone shows when magnified 1000 times there are visible microcracks about 10~50 μm; when magnified 2500 times there can be observed microcracks and grain dissolution hole.
Can be seen from the above analysis, B10 coal’s microcracks are more developed and has good connectivity, wide crack, and particle surface erosion is serious, and there are a large number of dissolution holes.
They have good connectivity and filling with strongly swelling sheet I/S mixed layer mineral among grains.
Compared with coal and sandstone, the microscopic structure of mudstone is relatively better, the number of microcracks and pores is relatively few, and the width of the crack is smaller.
Microcracks and pores are developed and have good connectivity and grain table is seriously corrosion

Table 1 Serial number and compositions of the SnO2 samples Sample No.
With 0.1 mol% Sb2O3 doped in the SnO2+0.5%CuO ceramic, the grain size undergoes a fast growing during the sintering process (Fig.2b): the high grain boundary mobility entraps small-diameter pores within the grains and at grain boundary.
However, when Sb2O3 increases to 0.5 mol%, the grain size is smaller and the relative density is higher (Fig.2c and Fig.1).
When the amount of Sb2O3 reaches 1.0 mol%, a large number of through pores are found at grain boundary (Fig.2d).

workpiece small abrasive grains big abrasive grainsLoad plastic agent semi bonded abrasive plate weight workpiece Fig.1 "Slump" mechanism of semi bonded abrasive plate Fig.2 Schematic diagram of Semi bonded abrasive lapping system In order to improve surface quality of Ge substrate efficiently, one effective strategy is increasing the number of active grains while maintaining processing load, which results in reduction of grits grinding force.
Semi bonded abrasive plate is manufactured of plastic agent, additive and abrasive grains.
Because of plastic agent, the big protruding abrasive grains will slump into plastic agent in processing, as it is shown in Fig.1.
The number of active grains will increase and the grain depth of cut will decrease.

In regions without cracks, grain size was normal and the ferrite was fine and distributed uniformly within the grains.
Such large grain size is much greater than the fine grain size of new solid forming on the mold wall.
In fact, Dippenaar has recently proposed that austenite grain size is influenced by the grain size of pre-existing delta ferrite, which puts blown grain formation at, or just behind the solidification front [6].
The average grain size was 1220±600 microns.
In reality, because of the nucleation barrier for the precipitation, the actual precipitation temperature will be lower and a sudden explosion in number of the precipitates is expected at lower temperature due to a high super saturation condition.

Contour numbers represent percent efficiency of dissipation.
At 900°C, the grains are broken and elongated which displays dynamic recovery appearing.
At 1100°C, the grain distribution is new and equiaxed grains nearly replace the original grains and the dynamic recrystallization fraction is dramatic increasing.
This is because that the grains have no enough time to recovery at larger strain rate [6-8].
(Item number: 50675146).