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The effect of abrasive grain size.
It can be derived that, as the particle size number of abrasive grains increases, the surface roughness decreases, and the smallest case happens when size number equals to 1000#.
Same as the traditional mechanical finishing, the greater the particle size number of abrasive grains is, the better the finishing surface roughness is achieved.
Therefore, within a certain grain size range, the surface roughness improved with the increase of the grain size number.
While as the grain size number is too large, the mechanical action goes weak and can’t match with the electrochemical action, and the residual passivation film makes the surface roughness increases.

PFZ can almost not be observed along grain boundaries in the alloys, where there are only a little of fine precipitates (as shown in Fig.2b).
It has been attributed to an increase in the number of the precipitates as the hardness increase with pre-ageing processes.
(2) The number density and size of precipitates are influenced remarkedly by the ageing processes.
The number density and size of precipitate leading to a hardness level is sensitive to the ageing processes
Forum Vol. 28 (2004), p. 429 Fig.4 Morphology of grain boundaries of 7075Li alloys treated by B4 (a)for 18h and (b) for 36h 0.1μm (a) 0.1μm (b)

As pointed out by Gao et al. [8], however, a limited number of reports have presented data on the wear behavior of HPT-processed materials and many of these results appear to be conflicting [9-12].
The grain size was about 15 µm.
The number of turns (N) was varied in five conditions: N = 1/8, 1/4, 1/2, 1, 2, and 3 turns.
It can be seen that the grain sizes for the specimens of N = 1/8 and N = 3 were 1.0 and 0.2 μm, respectively.
The grains were significantly refined with increase of N and r.

One is the theory of anisotropic grain boundary number, which was propounded by Coble [10,11].
In the former theory, the grain boundary number per unit length influences sintering shrinkage, because mass transport to neck occurs along grain boundary during sintering.
According to the grain boundary number theory, even spherical alumina particle compact aligned should hold isotropic sintering shrinkage, because the grain boundary number is isotropic in the compact.
The grain boundary number theory can not explain the sintering shrinkage anisotropy of spherical alumina particle compact with particle orientation.
However, this study does not exclude importance of the grain boundary number in ceramic compact on the sintering shrinkage anisotropy.

A number of the larger grains of the α-phase were also observed in the structure, which partially or completely lost its nearly lamellar structure.
All the EBSD maps were taken from a small number of grains of parent β-phase (Fig. 1c - two grains of the parent β-phase with similar orientations).
The number and type of Ci -matrices depends only by the type of lattice of the phase in which the transformation develops.
Acknowledgement This study was financially supported by the State Assignment, grant number 0836-2020-0020.
Winning, Five-parameter grain boundary analysis by 3D EBSD of an ultra fine grained CuZr alloy processed by equal channel angular pressing, Adv.

Fracture adjacent structure of fracture Middle structure of no fracture specimen specimen 100× 100× Stretch structure of fracture specimen 500× Stretch structure of no fracture specimen 500× Thread head structure of fracture specimen 100× Thread head structure of no fracture specimen 100× Fig. 3 Comparison of microstructures between fracture specimens and no fracture specimens According to Fig. 3, no significant grain coarsening or abnormal structure area was observed in both fracture and no fracture specimens (100×) with grain fineness number being normal.
Besides, the screw thread heads were also uniform tempered sorbite with same grain fineness number [5].
But the holes formed were quite special: some holes distributed along the grain boundary, some presented in the second phase particles position of the grain.
B element usually distributed at the grain boundaries and it is very important for grain boundary strengthening.
Therefore, B was extremely rare since it showed such high content in grain from the analysis experiment, which indicated that B element at the grain boundary would migrate into the grain and formed the second phase particles, resulting in weakening of boundary strengthening.

The result also shows that compression strength parallel to the grain for both wood species to be significantly different from those perpendiculars to the grain.
Two type of compressions test were carried out; axial compression (parallel to grain) and transverse compression (perpendicular to the grain).
Compression strength of Kapur and Kelat parallel to the grain and perpendicular to the grain were tabulated in Table 2.
The result shows that compression strength parallel to the grain for both wood species to be significantly different from those perpendiculars to the grain.
Tabarsa, Compression Perpendicular to Grain Behavior of Wood, Ph.D.

Grain size is refined from 33 µm in mill-rolled condition to 3.6 µm upon caliber rolling at 300 °C.
Total number of passes was 5 for each bar with 10% reduction per pass.
After caliber rolling for all the conditions, there occurs grain refinement.
The grain refinement for caliber rolling at 300 °C is noted to be maximum and the grains were equiaxed.
The probable reason for this is the maximum grain refinement achieved at this rolling condition, which has the equiaxed grains with size of 3.6 µm.

The fine-grained concrete without any reinforcement additives will have the minimum water absorption (3%).
Introduction Fine-grained concretes take a special place in modern construction.
However, in spite of all the advantages, they have a number of shortcomings, i.e. low bending strength, high shrinkage when hardening and, as a result, crack formation [1].
The fine-grained concrete without any reinforcement additives is distinguished with the minimum water absorption (3%).
Karpikov, Energy-efficient fine-grained concrete with integrated microfill, Construction and reconstruction. 5 (2014) 94–100

Several Ap grains were surrounded as a group by the pores, but additional heat treatment in a temperature range up to 900°C reduced the number of Ap grains in the group, and finally became a single grain region at 1000°C.
Several Ap grains were surrounded as a group by the pores, but the additional heat treatment in a temperature range up to 900°C reduced the number of Ap grains in the group, and finally became a single grain at 1000°C.
The size of Ap grains and pore density are closely related to the solubility and mechanical property of Ap ceramics, thus control of them is necessity [6].
The size and shape of Ap grains changed remarkably depending on the heat treatment, but the preferential alignment of Ap was never lost and still intensified.
Figure 4 Temperature dependence of grain size of Ap, relative intensity ratio of (002)/(310) and pore density in the Ap ceramics synthesized in this study. [5] T.