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The granules (or grains) of the abrasive, being relatively poorly bound between themselves, are slammed into processed surface by their grains which are bulged of the bundle.
Thus different normal forces N/Fi affect the nature of their mechanical contact with processed surface (where N - is a number of contacting grains).
Each of contacting grains of the considered granule is capable of delivering the certain force ( N/Fi ) (see fig. 1).
Interaction of the abrasive particle with rough surface Depending on orientation of the cutting edges of abrasive grains at forming granules there are three main types of the influence of abrasive grain upon the processed surface: cutting, plastic deformation and friction.
This layer covers the whole surface, hiding the borders of the grains.

Integrated fine grained security mechanism into different agents is the major feature of this model.
Integrated fine grained security mechanism into different agents is the major feature of this model.
· Integrate XML security specifications into multi-agents communication to provide a fine-grained security environment in CSCD [7, 8, 9].
Simple agents may only need a small number of modules (such as those for perception, reasoning and action) while complex agents will need more as shown in Fig 1.
· The X509IssuerSerial element, which contains an X.509 issuer distinguished name or serial number

Fig. 2(a) is the original H112 state, and a large number of elongated deformed structures can be seen.
Compared with the original H112 state, when the annealing temperature is between 320°C and 400°C, a large number of large-angle grain boundary grains appear at the grain boundary, and the proportion of large-angle grains on the L-S plane increases.
Fig. 2(d) shows more large-sized grains.
After the annealing temperature rises to 400°C, as the annealing temperature rises, the large-angle grains The grain ratio has not increased significantly, the grain size has not grown significantly, and the degree of recrystallization has not increased significantly.
It can be seen that in the H112 state, there are a large number of second phases in the plate, among which there are a large number of needle-like and small block-like second phases inside the crystal grains, and there are relatively coarse and irregular block-like second phases distributed along the grain boundaries.

The grain size remains the same and equal to 300 ÷ 500 µm.
At 1000 °C and strain rate = 10-3 s-1 fine recrystallized grains are formed at the boundaries of large grains (Fig. 3c).
Small recrystallized grains on the boundaries of the large, heavily deformed grains after deformation at the test temperature of 900 °C were observed (Fig. 5c).
The grains size of formed recrystallized grains is several μm and the volume fraction is less than 10% of the total volume.
With increasing of test temperature the intensity of relaxation processes increases and at the temperature of 1000 °C dynamic recrystallization occurs with formation of a large number of small recrystallized grains along the boundaries of coarse grains (Fig. 6c).

HPT is a highly effective SPD process that yields large volume fractions of high-angle grain boundaries (GBs), in which its grain refinement and homogeneity of strain distribution are governed by the number of revolutions of the lower anvil [7,8].
The equivalent von Mises strain, εeq. resulting from HPT processing can be estimated by the following equation, εeq = 2πrN/√3h, where r is the distance from the disk centre, N the number of HPT revolutions, and h the initial disk thickness.
Evaluation of grain shape, Acta Mater. 45 (1997) 587–594
Valiev, Grain boundaries in ultrafine grained materials processed by severe plastic deformation and related phenomena, Mater.
Birbilis, Effect of grain size on corrosion, Corrosion. 66 (2010) 1–4

A grain is represented by a polyhedron.
A grain is represented by a dodecagon.
Now let us consider how to express the nucleation number (γ) at time tni∆ .
A grain keeps growing until all of its facets are blocked by other grains.
Fig. 4a shows fine-grained α-Al2O3 scales. α-Al2O3 has close-packed hexagonal crystalline structure with space group cR3 (ITC number 167). αAl2O3 scales usually grow very much slower than other oxide scales, e.g.

Very Low-angle grain boundaries (VLAGB), Low-angle grain boundaries (LAGB) and High-angle grain boundaries (HAGB) were determined as boundaries with misorientation 1°≤ θ < 3°, 3° ≤ θ < 15° and ≥ 15° respectively.
Grains are elongated in the direction of material flow and newly formed small grains can be observed on the grain boundaries and inside the deformed primary grains.
(a) (b) Fig. 2 – IPF maps and IPF with density contours in ND and RD: (a) as-cast state, (b) 60% deformation The number of newly developed grains is increasing with deformation, while the overall grain size is decreasing.
The surface of each individual grain (S) was calculated by the grain detection, then the diameter of the equivalent circle area was calculated from the formula: d = 2 ∙ sqrt (S / π) and the average of those diameters give the average grain size to which was assigned the grain size no.
The newly developed grains have significant impact on the grain size, however the size of primary grains with HAGB is also decreasing with deformation (up to G9 for 70 %).

The SPD treatment would cause grain refinement in the copper matrix.
As a result, a submicrocrystalline structure is formed with average grain size ~800 nm, which also contains individual grains and conglomerates composed of up to eight grains.
The intermediate copper matrix layers separating Nb-Ti wire strands contain equiaxed grains having average size ~800 nm, while the outer copper layers have average grain size ~1050 nm.
Exactly the converse situation is observed for the copper matrix, i.e. the maximal number of characteristic X-ray photons is observed for Cu and the minimal number of the same photons, for Ti and Nb.
Then the number of characteristic X-ray photons of Nb and Ti would either grow or decrease depending on whether the number of the same photons of Cu grows or decreases.

Grain growth and movement [8]: links temperature field and liquid velocity to grain movement and growth.
Predicts grain morphology, secondary-dendrite arm spacing. 3.
Numbered arrows indicate a strong influence of one parameter on another.
Physical phenomena during: Microstructural Feature Descriptors Casting Homogenisation Grain and Cell Structure • Grain size • Grain morphology • Secondary-arm spacing • Grain nucleation (i, ii, iii) • Grain growth (i, ii, iii) • Grain movement (i, ii, iii) • Liquid feeding in mushy zone (i, ii, iii) Negligible changes Constituent Particles • Phase • Shape • Size distribution • Clustering • Number • Nucleation (iv, vi) • Growth (iv, vi) • Competitive phase selection (iv, vi) • Growth Morphology • Phase transformation (ix, xi) • Thermal break-up • Coarsening and spheroidisation Dispersoid Particles • Phase • Shape • Size distribution • Number • Nucleation (viii) • Growth (viii) • Nucleation & Growth (x, xii) • Coarsening and dissolution (x, xii) • Transformation (xii) Solute Level in Solid Solution • Spatial distribution of each element (across cell) • Non-equilibrium solute distribution
• dispersoid size and number affecting pinning of dislocations and GBs.

Fig. 2 SEM images of the three kinds of powder（a）LAP100.29; （b）ABC100.30; （c）Experimentation powder 3.5 Impact analysis of reannealing on particle hardness, grain size, the number of crystal grain and compressibility.
According to Hall-Patch formula, σs =σi+Ksd-1/2, as the number of crystal grains is reduced (the grain size d increases), the yield strength of the material and plastic deformation resistance decrease, which can help to improve the density of compacts.
In addition, reduction also helps to reduce the number of crystal grains.
Compared with Figure 4, which is the Höganäs ABC100.30, the number of crystal grain in Fig 3 has no significant decrease.
Fig. 3 The number of crystal grain of Fig. 4 The number of crystal grain of LAP100.29 after reduction at 950 ℃.