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Moving speed of the abrasive grain at a fixed point in time depends on the path of the grain.
The more deeply embedded in the grain surface to be treated, the more uneven the abrasive grains are cutting part of his profile.
For example, aluminum oxide grain for rounding radius cutting grains: Where - a diameter abrasive grain, mm.
With increasing tip radius of the grain becomes more solid, and the grain begins to cut thicker chips.
The vast number of abrasive grains makes full sections, i.e. when they relate to the treated surface and out of contact with the surface at a depth of cut close to zero.

Generally speaking, the burning area of grain changing with time is the key to the grain combustion simulation.
Wang et al uses 2D level set to simulate the anisotropic SRM grain burning[8], Qing [9] demonstrates the application of level set in grain burning surface calculation.
SRM grain surface regression simulation SRM grain is a kind of high-energy fuel which propels the whole missile to attack enemy target.
At last the whole grain will burn out.
It is found that two methods can get very close results except the end of the curve because of the number of finely triangles increasing.

Significant degradation is observed in the coarse grain material and a marked sensitivity to the loading level is outlined.
Figure 3 shows the influence of the load level Rf (ratio of maximum applied load and the monotonic load at steady state of bridging) on the variation of φ with the number of cycles for the coarse grained material A20.
What is important is that the threshold of cyclic crack propagation tends toward that of the fine grained material.
Lawn, "Cyclic fatigue from frictional degradation at bridging grains in alumina" J.
Dauskardt, "A frictional wear mechanism for fatigue-crack growth in grain bridging ceramics", Acta.

It has been shown that the grain size and the size of intermetallic phases and their distribution are strongly dependent on the ECAP process parameters, primarily on the number of passes through the ECAP die.
After low number of passes, the obtained structure is not fully homogenous.
Areas with larger grains and areas with smaller grains coexist in the structure; with increasing number of passes the homogeneity increases.
After low number of passes also large unchanged Mg17Al12 particles remain in the structure.
The microstructure of AZ91 depends on the number of ECAP passes and also on the initial size and morphology of Mg17Al12 precipitates.

Although a considerable number of studies have been made on the mechanism of the preferred growth of Cube texture [6-8], there is lack of spatially resolved crystallographic data directly related textural development at an early stage of recrystallization.
In the Sample-A, the fraction of Cube orientation increased sharply from 558K to 578K with increase of the number of new Cube grains.
To put it another way, one explanation for the preferred-growth orientation, such as Cube in the Sample-A or S in the Sample-B, can be that the number of growth grains is more than that of shrinkable grains.
On the contrary, regarding the shrinkable orientation, such as S in the Sample-A or Cube in the Sample-B, the number of shrinkable grains is more than that of growth grains.
Even on a large grain that grew remarkably, some grain boundaries were hardly moving in the direction of the surrounding grain that had higher grain boundary mobility.

The average grain size reached to ~ 3mm.
The size of the fine and dispersed particles was only several nanometers and the particle number density (Nv) was very high.
More importantly, the particle number density (Nv) of each alloy is quite different.
There are some particles precipitated on trigeminal grain boundaries which can obstacle the movement between the grain boundaries to some degree.
The main reasons for the good performances are supposed to be the high number density of precipitates, ultra fine grains and the thermal ability ternary phases.

The recrystallized grain size in the easy deformation zone is reduced with the number of forging passes, and the area of recrystallize grains increase with the number of forging passes. 1.
With the number of forging passes is increased to 6 and 9 (true strain of 3 and 4.5), the hardness along the center line of the samples is similar to that of the 3 forging pass ingot, while, the maximum hardness value near the edge increases with the number of forging passes.
The cumulative true strain increases both in easy deformation zone and stagnant zone with increase the number of forging passes.
Although there are no recrystallized grains in the stagnant zone as the true strain increase to 1.2 (3 passes), 2.4 (6 passes) and 9 (passes), the hardness of the stagnant zone decreases with the number of forging passes indicating that dynamic recovery has happened. 5.
(3) The recrystalized grain size in the easy deformation zone is reduce with increasing number of forging passes, and the area of recrystallized grain get larger increasing number of forging passes.

Grain size distribution in the sinter is an important index sign to measure the quality of sinter.
Calculation of Fractal Dimension for Grain Size Distribution Set the total weight of broken model invariant, each composition, will the part of the probability P which in the original grain (here, the probability P is connected with the broken body of their own strength and experimental condition) as the split ratio r to reduce the size, infinitely repeat, then generated a series of grain groups that was large and small, calculate the fractal dimension of grain group as follows, multiply the amount of re-construction the N grain is [2,3]:
The fractal dimension D [4] of grain group is:
Macroscopically, the sinter ore, which falls from a certain height and the lumpiness and the shapes difference, is combined with a number of different size massive sinter with the pore.
Therefore the fractal dimension D for grain size can be conveniently calculated by the Eq. 3.

Unique features of ultrafine-grained microstructures in materials having low stacking fault energy Jenő Gubicza1,a, Nguyen Q.
It can be seen that the size of the recrystallized grains is ~1 µm.
In severely deformed polycrystals, the magnitude and direction of the internal stresses change from grain to grain, so that the probability of annihilation of dislocations depends upon their specific locations within the specimen.
By increasing the numbers of passes up to 8, the mean dislocation density measured immediately after ECAP is increased and accordingly the rate of recrystallization should be faster after larger numbers of passes.
With increasing numbers of ECAP passes, there is an increase in the contribution from twinning which appears to facilitate recrystallization.

Introduction Severe plastic deformation breaks down the microstructure into finer and finer grains.
It is generally identified that the ultra-fine grained (UFG) structure exhibit a number of beneficial physical properties [4-7] (mechanical properties, elastic and damping properties, fatigue and creep, etc) in comparison to coarse grained crystals.
According to MiloŠ [8], the corrosion damage is more homogenous in the ultra-fine grained materials and the clear localized intergranular corrosion in coarse grained material.
The corrosion damage of UFG copper is macroscopically rather uniform whereas an obviously preferential grain boundary degradation and selective corrosion of some grain interiors was observed in CG copper.
The average grain size of Cu was refined to about 300 nm by ECAP for 12 passes.