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Lapping is carried out by applying loose abrasive grains between two surfaces and causes a relative motion between them.
During process, the mechanism of surface formation are decisively affected by a pressure force, a process time and a motion type of grains.
Lapping is carried out by applying loose abrasive grains between two surfaces and causes a relative motion between them resulting in a finish of multi-directional lay.
Moreover during machining, the mechanism of surface formation are decisively affected by a pressure force, a process time and a motion type of grains [4, 6, 10].
However, it was observed that better conditions can be obtained when the number of motions made by conditioning ring during a full rotation of lap equals i=0,5.

And the function of cutting is main completed by the abrasive grain which is sticked in the basement.
In order to effectively reduce the number of tests and identify the main rule of impact at the same time.
Through the analysis of variance of the test data is not difficult to drawing the follow conclusion: Abrasive grain is the most significant impact on the surface roughness of hydraulic piston rod, which mainly reflect geometry relationship between workpiece and abrasive grain.
Therefore, we should increase fineness number of the abrasive belt and increase appropriate the line speed of abrasive belt as well as choose the right feed speed and contact pressure in order to reduce the value of the surface roughness.
Factor Test number [4] A.

The first extruded micro-gear, that modulus m = 10μm, number of teeth z = 10 micro-gear, was carried out by SAOTOME and IWAZAKI of Japan GUMA University using Al78-Zn superplastic materials in 2001[1-2].
In this paper, the basic parameters of the micro-gear studied are as follows: modulus m = 0.125 mm, pressure angle α = 20°, number of teeth z = 6, addendum circle diameter d = 1mm.
The recrystallized grains, nearly spherical grains, of the blank after hot extrusion are shown in Figure 5(a).
According to Figure 5(a) and Figure 5(b), the grain size of the micro gear extruded would be more smaller than that of its blank, that means, brass H62 would was refined by extrusion process.
The grains of the micro gear were elongated during the hot extrusion process, so that there was fibrous tissue to be happended along the direction of deformation, by which the anisotropy mechanical properties to be formed. 3.

It is found that the optical gap of these layers decreases from 3.87 to 3.58 eV, and the grain sizes decrease from 35 to 30 nm.
The grain size of the layers was calculated using X'Pert High Score.
The texture coefficients TC(hkl) have been based on the following formula (Eq. 1) [21]: TC(hkl) = I(hkl)/I0(hkl) N−1 ∑N n I(hkl)/I0(hkl) (1) where TC(hkl) is the texture coefficient of the plane (hkl), I(hkl) is the measured intensity, I0(hkl) is the standard intensity, N is the reflection number and n is the number of diffraction peaks.
The grain size (D) decreases from 35 to 30 nm.
It is concluded that the optical band gap of the thin film layers decreases from 3.87 to 3.58 eV and the grain sizes decrease from 35 to 30 nm.

The interfacial transition zone “perlite grain – cement stone” was examined in order to reveal features of its formation.
These features allow to create a dense and strong shell/caging around the perlite grain which helps to avoid its corrosion and produce perlite concretes with high durability.
Since an expanded perlite is a chemically active aggregate, with time the perlite grains in the interfacial transition zone "perlite – portland cement" start to corrode.
Its microhardness is by 20 – 25 % higher than that of the cement stone in the space between the grains.
Acknowledgements This work was financially supported by the MSM 0021630511 research project and state budget via Ministry of Industry and Trade of the Czech Republic (project TIP, number FR-TI2/340).

More Se supply by increasing Se evaporation temperature or by increasing the flow rate of carrier gas resulted in the larger CIGS grains.
When A zone temperature was 450 o C, it was observed that individual nanoparticles were merged into a larger grains.
It can be inferred from this result that we can get larger grains of CIGS as the flow rate of carrier gas becomes higher and higher.
The formation of MoSe2 layer is attributed to the direct contact of Se vapor with Mo layer through the larger number of pores in the CIGS layer.
Conclusions As spray deposited CIGS layers could not be used as absorbers because of low crystal quality and small grain sizes.

Necking and ductile fracture are observed for all samples with a significant number of dimples, voids and tongues formed.
In Fig. 1c, a few large grains can be observed using polarised light with pronounced grain contrast and grain boundaries.
These recrystallised grains (Fig. 5b) are significantly smaller (~10 µm in size) than the grains observed in Fig. 1c.
It is noted that the IMCs are located near and/or at the newly formed recrystallised grain boundaries implying that the IMCs act as a stress concentrator and leading to nucleation of grain boundaries.
The neck is formed for samples at all tested strain rates, leading to a ductile fracture with a significant number of dimples, voids and shear plates.

As a first approximation, it is assumed that the stored energy is uniformly distributed within the deformed grains.
Therefore, the only factor that varies within a deformed grain is the rVf / ratio of the dispersoid particles.
In commercial aluminium alloy hot rolled plate, it has been demonstrated that particle stimulated nucleation (PSN) of recrystallization at coarse constituent particles located on grain boundaries is the primary initiation mechanism for new recrystallized grains [2].
Zr / at.% Cu Mg Zn Zr Centre Edge 0 0.5 1 0 10 200 0.5 10 200 400 Radius Number density 0 0.5 1 0 Radius / nm 0 0.5 10 200 400 Number Density /µm-3 Radius Number density Distance Centre Edge 0 0.5 1 0 10 200 0.5 10 200 400 Radius Number density 0 0.5 1 0 Radius / nm 0 0.5 10 200 400 Number Density /µm-3 Number Density /µm-3 Radius Number density Distance Centre Edge Distance Centre Edge (a) (b) Fig 2: (a) Distribution of alloying elements across a typical dendrite (centre to edge) in AA7050 (0.13wt% Zr) predicted using a Scheil model.
To investigate the significance of each of these variables, commercially rolled 7050 plate was studied using EBSD and FEGSEM to determine the as-rolled grain and subgrain structure and number of particles above the critical size required for PSN.

Characteristics of the grains and grain surfaces were observed by Transmission Electron Microscope (TEM) with conventional and high resolution techniques, (JEM-2010), JEOL, Japan).
Zirconia grains could be observed in the powders having higher additions of Zr(OPr)4 (> 20 wt. %).
Size Table 1 shows the correlation between calcination conditions and avarage grain size from XRD analysis.
The TiO2 grain size was increased with higher calcination temperatures.
Acknowledgement The work is a part of the project supported financially by National Metal and Materials Technology Center (MTEC) under project number MT-B-48-CER-07-190-I.

X-ray diffraction analysis indicated the reaction products to be crystal grains of nickel atoms and intermetallic compound of Ni3P.
In addition, during the piling and thickening process of coating, rare earth metal Ce could also lower grain boundary energy, hinder movement of crystal boundary, thus helping tightening surface structure during the thickening of coating.
Significant discrepancy in depth, width and location of the peak in picture 2, suggested structural transformation of crystal grains with better thermodynamic stability tended to happen under higher temperature, while the growth of crystal grain of Ni took place under a lower temperature approximately about 340.44℃.
Meanwhile, due to the relatively strong catalyst power of the coating already piled on the substrate, the number of nucleus formed will increase.
Quicker stirring and faster precipitation of hydrogen increased the transfer rate of atoms, and great numbers of these interconnected crystal grains on the flat surface caused the surface structure to be more compact, leading to the formation of microcrystal.