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is the ordered number of nodes counting outward from the center?
Electroplating basement material is metal nickel (Ni); abrasive grain cluster is comprised of metal nickel (Ni) and CBN abrasive grain.
From Fig.3., Fig.4. and Fig.5., we known that the grain distribution and pore ration on the wheel surface can be changed by the changing of the phyllotactic parameters r, k, , so that the specific energy consumption, chip space, effective grind grain number and cooling fluid flow etc can be controlled when the workpiece is ground, specially, the leaves column line groove can be formed when the abrasive grain clusters are arranged based on phyllotactic pattern, cooling fluid can flow along the leave column line groove, so that the grinding heat damage is decreased and grinding scraps are removed quickly.
(a) Omitting abrasive grains, (b) omitting abrasive grain clusters, (c) the half-baked form of abrasive grain clusters, (d) rough electroplating coating . 600µm (b) Abrasive grain cluster 600µm (a) Grain Conclusions A superabrasive grinding wheel has been design based on the phyllotactic arrangement of sunflower seeds, and then the superabrasive grinding wheels with phyllotactic pattern are fabricated.
When the abrasive grain cluster radius is r=0.3～0.8mm, the changing of the abrasive grain cluster radius is small influencing to the developing of electroplating layer, electroplating processes influence the electroplating quality and the abrasive grain distribution within the abrasive grain cluster.

As seen in Fig. 1b, when the annealing temperature increased to 300 ℃, the aluminum matrix were fully number of recrystallized grain increased and the size became larger compared to 1 h annealing at 250 ℃ (Fig. 1b).
According to Fig. b-d, it can be found that after 300℃, with the annealing temperature further ascending, the number and size of recrystallized grains hardly changed.
As the annealing time increased, there was no significant change in the grain size of recrystallized grains.
In the GOS maps, “blue” grains (misorientation angle less than 2°) denoted recrystallized grains.
The graphene was homogeneously dispersed at Al grain boundaries, and the presence of graphene would prevent grain boundary migration and restrict the growth of grains [4, 14, 18].

Coarsening of deformed grains is not permited.
Results For the examination of grain coarsening every cell is considered as a whole grain.
Example grain structures from the simulation of grain coarsening.
Results of the simulation of grain coarsening.
Average grain area (in the number of cells, c) as a function of time (in the number of steps, cas) (a), and the rate of the grain coarsening as a function of 1/T (b).

Austenite grain size conforms №6 and 7 in grain fineness scale compliance.
Austenite grain size conforms №6 and 7 in grain fineness scale compliance.
Austenite grain size conforms №6 and 7 in grain fineness scale compliance.
Austenite grain size conforms №6 and 7 in grain fineness scale compliance.
Former austenite grain size conforms №6 in grain fineness scale compliance.

Ultrafine-grained (UFG) commercially pure (CP) Ti with a grain size of about 200 nm was produced by ECAP up to 8 passes using route BC at room temperature.
The applied strain rate is always indicated by numbers, e.g. ‘‘-3’’ stands for a strain rate of 10-3 s-1.
This indicates that the deformation in UFG CP-Ti is controlled by the grain boundaries, such as grain boundary sliding, grain boundary diffusion and Coble creep.
The average grain size was measured to be about 200 nm.
The deformation in UFG CP-Ti, besides the classical deformation by dislocation slip and deformation twin, is controlled by the grain boundaries, such as grain boundary sliding, grain boundary diffusion and Coble creep.

Besides focusing on the number of applied dimensions, a novel approach was introduced by Y.Wang et al. [5], who regarded the wheel surface to be consisting out two characteristic wavelengths.
As a result, the number and configuration of the abrasive tool points in the grinding wheel surface have been derived.
The dimension of grains are not a constant number, instead they comply with a normal distribution.
In the model the Monte-Carlo principle is applied to generate the grain diameter number which complies with the normal distribution N(Dnorminal, σ).
The static grain count is defined as the number of abrasive grains per square millimetre on the wheel surface.

This may be seen in Fig.1 where the nucleation of grain number Three was not obvious until about the 12 min. mark.
In general this behavior was observed for all grains with the exception of the grain designated number Four.
The grain number Four data shown in Fig. 2 was anomalous in that there did not appear to be a rate change when the temperature was raised from 150° C to 160° C and all growth ceased before the temperature was lowered back to 150° C.
Only grains numbered One and Seven were similar in most respects except for the initial velocity.
The apparent activation energies from the three grains that could be analyzed were 119, 127 and 143 kJ/mol for grains numbered Two, Three and Six respectively.

In recent years, for grain refinement, severe plastic deformation methods has been used.
A similar technique appears to be ECAP-Conform as a continuous processing of ultra fine grained Al (Fig.5) [7].
Results and discussion Pressing pressure versus number of passes by route A, for fixed and movable die walls, is shown in Fig.7.
The ECAE pressure has increased slightly with increasing of number of passes due to strain hardening.
Hardness, 0.2 % yield stress and fracture elongation versus number of ECAE passes are presented in Fig.8.

In Fig. 3 (a), after 1 pass deformation, the microstructure still retained a large number of coarse original grains, which contained a densely distributed fine-lamellar LPSO phase with uneven grain size.
There were a large number of fine grains, which were typical DRXed grains.
A large number of LAGBs were also distributed in the grains of the fine grain region, indicating that the DRXed grains were also gradually refined.
With the increase of deformation, the blue points increased, indicating that the number of the DRXed grains increased.
It can be inferred that with the increase of processing passes, the number of unDRXed grains decreased while the number of DRXed grains increased.

Austenite grains did not coarsen for 60 s, see Fig. 1a-c.
The effect of prior deformation is to accelerate recrystallization nucleation kinetics, which can be related to the number density of austenite grains.
Effect of solute niobium on coarsening kinetics of austenite: The driving force for grain coarsening is the reduction in surface energy associated with grain boundary, expressed as: G=2γR (1) The boundary mobility for plain C-Mn steel as determined by Zhou et al. [4] is: MC-Mn= 0.192Tt exp-20,837Tt m4/J s (2) This is modified to incorporate solute drag effect which was modeled using Cahn’s equation [5] Mgbt=1MC-Mn+αCNb-1 m4/J s where, α=δNvkBT2EbDsinhEbkBT-EbkBT (3) MC-Mn and CNb refer to the intrinsic grain boundary mobility of the C-Mn steel and the concentration of Nb in solution respectively, δ is the grain boundary width ∼1 nm, Nv is the number of atoms per unit volume, Eb is the solute-boundary binding energy (20 kJ/mol) and D is the trans-interface boundary diffusion which is equal to twice the bulk diffusion coefficient of Nb in austenite [6].
Table-1: Effect of austenite grain size and % reduction below temperature of no recrystallization (TNR) on Sv factor and ferrite grain size.
Thus, the key to obtaining target ferrite grain size in API –X-70 in high Nb microalloyed steel in compact strip rolling is to refine the austenite grain size by static recrystallization and take advantage of solute drag due to high niobium to prevent grain coarsening of grain refined austenite as in OHTP process.