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First of all, a comprehensively accepted burr definition would be required, but it proved a very difficult task, because a number of experts has carried out studies in this field, and they have established their own various burr-definitions.
Magnetic Abrasive Barrel Deburring (MABD) A number of methods have been suggested for abrasive-grinding in magnetic field [5], one of them is the so called magnetic abrasive barrel deburring method.
According to this method, the abrasive parts (grains or pellets) and the workpieces are loaded into a revolving plastic container, with the ferromagnetic part of the barrel’s contents being restrained by magnetic shoes enclosing the rotating barrel.
The grist or flour fills the cavities of the grains, and this way the grains glide over the fine surfaces of the workpieces without scratching them while the sharp burrs will be removed.
Features of the brush were: diameter Ds = 100 mm, trim length ℓs = 37,5 mm, diameter of filaments ds = 1,38mm, size of ceramic grains: 80 mesh.

Meso-scale parameters such as co-ordination number, distribution of contact normal and contact forces are studied under cyclic loading.
The particle generation for the above cases was accomplished using a random number generator.
The average co-ordination number, = M/N, of the assembly is defined as the ratio of the total number of contact points (M) within the assembly volume to the total number of particles (N) in the assembly.
The development of average co-ordination number of assembly with the number of load cycles is showed by Fig. 2.
The results that sand grains’ realignment namely is stress-anisotropy during liquefaction stages also are drawn.

After crushing, grinding and screening, the grain size of minerals used in flotation tests were -0. 106 mm +0. 044 mm.
The chemical elements of lizardite were analyzed by XPS, and the grain size of minerals were -5μm.
Table 1 The electron spectroscopy for chemical analysis Mineral Chemical elements Electron binding energy（eV） Electro valence element content（%） Lizarite Si2p 101.0 +4 19.04 O1s 529.8 -2 64.34 Mg1s 1303.3 +2 16.62 Lizardite Figure 1 The XPS analysis of Lizardite By the XPS analysis, mineral surfaces were with a large number of metal ions and oxygen ions, and the content of these elements was closely related with the crystal structure.
Table 2 The calculation results of bonds of Mn+-O2- of lizardite Minerals Lizardite Cations（Mn+） Mg2+ Si4+ Electrovalence(Z) 2 4 Ionic radius (Rc)（nm） 0.072 0.034 Coordination number(n orCN) 6 4 Electronegativities of elements 1.31 1.74 Electrostatic valence strength (S=Z/n) 1/3 1 Average bond length（nm） 0.210 0.162 Electrovalent bond rate（percent） 73.66 53.90 Coulomb force（×10-8N） 2.400 3.556 Electrovalent bond polarity 0.78 0.626 Bonding intensity () 0.14~0.19 0.78-1.11 Average bond valence 0.331 1.02 Through the analysis of lizardite crystal structure and calculation of chemical bond ,we can know that: during the grinding process, lizardite surface bond breaking easily occur in the hydrogen bonding, the Mg-O bond and a small amount of Si-O bond, so that unsaturated Si-O-Si, O-Si-O, magnesium containing keys, hydroxyl and hydrogen bond of reactive groups were produced in the lizardite surface .

Design of experiment (DOE) is an optimization method used to identify significant influencing factors of experimental processes and model factors and responses with a minimal number of experiments.
Commercial HA (Fluka) and β-TCP (Fluka) powder were mixed and shaped into a number of pellets using conventional ceramic processing route which involved wet mixing, pressing and sintering.
From microstructure images in Fig. 2, there are different of grain size at different sintering temperature.
At 1250°C, the grain size is smaller than at temperature 1100°C.

Adding TiB2 in Al2O3 ceramic can inhibit the growth of Al2O3 grains make composite ceramics with high hardness and high strength, and dispersed TiB2 particles may hinder crack propagation, to improve the fracture toughness of a certain role[4-7].
As can be seen from Figure 1, after mechanical alloying process 4 ~ 16h, the diffraction peaks of Al, Ni and TiO2 are decreased, indicating that they are constantly decreasing grain size; until 20h after mechanical alloying later, and the diffraction peaks of Al and TiO2 disappeared, simultaneous appearing the diffraction peaks of Al2O3 and TiB2, indicating that the mechanical alloying process 16 ~ 20h, the reaction 10Al + 3 TiO2 + 3 B2O3 = 5 Al2O3 + 3 TiB2 occurred.
As can be seen from Figure 2, after the mechanical milling 4h, a large number of smaller size particles adsorbed on the surface of larger particles, more particles formed agglomeration, because during the milling process, the raw powder plastic deformation and cold welding makes the particles are composite particles at high speed steel ball collision and extrusion.
After ball milling 8h, there are a lot of the composite particles at this time, and a large number of smaller size particles appearing.

Above 5800rpm, the number-average diameter is lower than 20μm with a bimodal particle size distribution.
Compared with by ingot metallurgy (IM), high Nb containing TiAl alloys can be processed by powder metallurgy with a high degree of homogeneity and a fine grain size.
After heat treatment, the alloy ingot exhibits FL microstructure without β phase or Al-rich phase segregations, Fig. 2(c) and (d), and the average grain size and lamellar spacing are 320μm and 0.8μm, respectively.
The number-average diameter, D(1,0), sharply decreases with the rise of F value.
At or above 5800rpm, the number-average particle size is largely lower than 20μm.

The SEM image reveals the grains nucleate in a cube-like shape.
The experimental data matched well with the simulated patterns from crystallography open database number 9008068.
As shown in Figure 3, the SEM image reveals the grains nucleate in a cube-like shape.
The grain size calculated from the SEM image varied from 300 nm – 1500 nm.
(a) SEM image of FeMnO3 reveals the grains nucleate in a cube-like shape.

Increased grain size can disrupt the regularity of the crystal lattice.
The doping process can produce aberrations in the crystal lattice and increase grain size, resulting in broadened peaks.
The average grain size was calculated as 613nm.
These numbers provide information on the thin film's microstructure and crystallinity, which might influence its qualities and possible uses.
SEM analysis confirms the non-uniformity of deposited thin film of irregular shaped bead-like structure with grain size 613.3 nm and due to high absorption, it is used in solar cell applications for high efficiency.

Grain boundary can be observed obviously with optical microscope, and the sharp of grain is pentagons or hexagons.
Grain boundary of translucent material can be observed obviously by optical microscope, and the sharp of grain is pentagons or hexagons.
AgCl in electrodes sintered by direct heating method shows the trend of the formation of hexagonal grain boundaries, indicating the crystallization trend of AgCl, it may bring harmful effect to the stability of electrode potential.
The cabined spaces are not conducive to migration of internal gas diffusing to outside, bring a number of salient protuberance on the surface.

We observed clearly grain boundaries (GBs), twin GBs, stacking faults and etch pits.
The dislocation density of middle part was minimal for there were few impurities, small undercooling, bigger grain size and columnar crystals growth sufficiently.
Moreover, we also found the number of etch pits of edge was larger than center for each wafer.
Effect of drop-down rate on the growth orientation As can be seen from Fig.3, the columnar crystal grew orderly and the grain size was bigger when the drop-down rate was 20μm/s.
When the drop-down rate was 10μm/s, the grain size was big since the slower solidification rate and time enough to growth.