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The grinding wheel used for experiments is shown in Figure 2, its diameter is φ300mm, the size of the CBN abrasive grains is 70/80Mesh, the distribution density of the grains is 1.3/mm2.
In cylindrical coordinate system, its mathematical equation is as follows: ，，（1） Where, n is the ordering number of a seed, counting from the bottom of the cylindrical surface.
Each seed was considered as a grain that is distribute on the grinding wheel surface.
The reason is that, when the abrasive grains are arranged with phyllotactic pattern, the abrasive gains can obtain the biggest packaging on grinding wheel surface, thus the effective grain numbers on the surface of grinding wheel with abrasive phyllotactic pattern  are more than the other configurations, meanwhile, phyllotactic configuration of abrasive grains can generates the abrasive Fibonacci spiral lines, and between two spiral lines, a channel is generated, which can make grinding liquid effective flowing, therefore its grinding performance is relatively good.
High-performance dry grinding using a grinding wheel with a defined grain pattern[J].

Dense compacts with grain sizes in the nanometer to micrometer range were processed.
The average grain size of HA compact sintered at 1000 °C was around 500 nm.
Grain size increased to 3 µm when the compacts were sintered at higher temperature.
Bone and joint diseases account for half of all chronic conditions in people over 50 years of age and the number of people suffering from this diseases are expected to increase steeply around the globe by year 2020 [2].
These authors claimed that below some critical grain size, the hardness is governed by relative density and above that size; grain growth is the controlling parameter.

The number of cars is also represented.
The grain size is almost unchanged when Ag is added.
However, when Mn is added the grain size becomes very small.
In the Ag-added alloy the number density of nanoclusters and the eta prime precipitates is higher.
Fig.11 Optical and TEM micrographs showing grains and precipitates near grain boundaries (PFZ) in Al-Zn-Mg, Ag-added and (Mn+Ag)-added alloys [1,5,6,7].

The equiaxed grains were found in the 7Zn, 11Zn and 49Zn specimens.
P. zone formed on grain in quenched Al-Zn alloys.
Under constant initial deflection conditions, the vibration number for the 83Zn specimen was lowest, and the vibration number increased with decreasing Zn content (see Fig. 5).
For the AZ91-F specimen, no deformation twin was found in the grains, and a larger number of precipitates and proeutectic formed in the matrix.
Notably, a very small number of precipitates still existed in the AZ91-O matrix and they were Al-Mg-Mn compounds.

The result was a 'bimodal' structure of micrometre-sized grains (at a volume fraction of around 25%) embedded in a matrix of nanocrystalline grains.
The approach introduced in [1,8] is based on the formation of ultrafine-grained structures with high-angle and non-equilibrium grain boundaries capable of grain-boundary sliding (GBS).
It should be stressed that recent experiments investigating deformation mechanisms in nanostructured materials have confirmed a number of the results of computer simulation [16,26,27].
A possible explanation is that diffusion may be faster in SPD-produced ultrafine-grained materials with highly non-equilibrium grain boundaries.
The starting Al wire had a grain size of 5 -7 µm.

There is a sufficient number of possibilities to increase the strength of the alloy; among them there are grain boundary (Hall-Petch) strengthening [10], work hardening [11]; and precipitation strengthening [10].
The size of the fcc grains was ~250-400 μm.
The grains had an irregular shape.
Some coarser carbides were also found on grain boundaries.
One has also note that carbides are likely to restrict grain growth in the fcc matrix; the grain size in the equiatomic CoCrFeNiMn alloy after the same processing is several times higher [9].

For investigating the loads on diamond grains, the average normal force per grain and the average tangential force per grain are obtained as: 'n n c F f C lλ = , 't t c F f C lλ =
The active grain density C for the diamond wheel was obtained by counting active diamond grains observed on all the segments using an optical microscope.
The maximum grain depth of cut, which is a measure of the cutting severity at individual grains, can be written as [7]: 0.5 0.25 3 ( ) ( ) tan p w m s s av h Cv d λ θ =
fn (N/grain) 0 5 10 15 20 hm (µm) 0 20 40 60 80 ft (N/grain) 0 1 2 3 4 ap=2-30mm vw=22-150mm/s vs=50m/s vs=60m/s vs=70m/s vs=80m/s Fig.5 Forces per grain versus maximum grain depth of cut 2θ hm lc lc From the net spindle power, the specific energy u, which is defined as the energy per unit volume of material removal, can be calculated as [7]: ' p w P u a v =
The highest value of u in Fig.6 is three times greater than our previous results of sawing same granite at vs=30 m/s. 0 20 40 60 80 u (J/mm3 ) 0 2 4 6 8 hm (µm) ap=2-30mm vw=22-150mm/s vs=50m/s vs=60m/s vs=70m/s vs=80m/s Fig.6 Specific energy versus maximum grain depth of cut To understand the contribution of vs to u, it is necessary to mention a quantity Sw', which is defined as the plowed surface area generated per unit time per unit width and can be obtained by multiplying the plowed area for a single undeformed chip by the number of abrasive grains passing through the cutting zone.

In each sample, the sizes of over 2000 grains were measured to calculate average grain size d.
A small number of unrecrystallized grains with size about 20 μm and with a large aspect ratio along ED had an area fraction of about 31%.
All the recrystallized grains around the elongated grains were high-angle grain boundaries and the misorientation was larger than 15°.
In slip dominated grains, a mass of dislocations piled-up at the grain boundaries, where the grain boundaries were warped with seriously crystal lattice distortion [17].
The new grains nucleated at the original grain boundary and were distribute annularly around the original coarse grain [18].

The grain size of equiaxed nanocrystallites with random crystallographic orientations on the top surface layer was about 10nm.
The sample surface to form a uniform distribution of the grain size of equiaxed nanocrystals, grain size is concentrated within a range of about a few nanometers to tens of nanometers, the average grain size of about 10nm.
The Octavia and continuous diffraction rings show that there are a large number of crystal grains, and having a large angle between each other and the random orientation difference in the diffraction region.
Pre-pressure rolling technology surfacing repair the surface prepared nanocrystalline layer the surfacing layer surface nanocrystalline layer grain refinement and uniform, small grain size, around about 10nm.
Microstructure and evolution of mechanically-inducedultrafine grain in surface layer of AL-alloy subjected toUSSP[J].

However the existing large-grained component in the enterprise service system are hard to satisfy the requirements of efficient reuse and development.
However the existing large-grained component in the enterprise service system are hard to satisfy the requirements of efficient reuse and development.
High-level components can be decomposed into a number of low-level components and served as a guide to low-level ones.
Table 1 shows the specific number of leaf node underlying the component tree, and then the product application service functional components with high reusability can be obtained with the corresponding composition strategy.
However, existing component composition techniques have limitations in effectively supporting multi-grained components.