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Important properties for tribological behavior are as following: grain size is 0.491 mm, surface hardness is 2,874 HV and fracture toughness is 3.0 MPa×m1/2.
Sever abrasion causes rubbing of sharp diamond grains.
As sliding distant increases, roughness values of diamond grains fluctuate between 12 and 18 nm.
In Figure 7b, protrusions of diamond grain become flat, concentration of diamond grain is less than the new condition in Figure 7a, and some areas are partly covered by wear debris of worn AlTiC material.
The project is partially funded by RRI-MAG project number MSD-5610021, and Western Digital (Thailand) Co., Ltd.

The as-received plates with a thickness of 6 mm possessed nearly equiaxed grains with 8.9 µm in size.
Equiaxed grains with an average size of 12.4 µm were formed in HR sheet, and small amount of twins were observed within grains.
Equiaxed grains with an average size of 14.2 µm were formed in AHR sheet.
A number of twins were observed within grains compared with those in symmetrically rolled sheets.
Consequently a lot of recrystallized grains with various orientations were generated.

In the experimental part the comparison of two alumina-chromium composites, first based on the aluminium oxide powder with average grain size about 1 mm and second with average grain size about 80 nm is shown.
Material preparation In the present work two types of ceramic powder were used: - aluminium oxide, a-form, purity 99,99%, average grain size 1 mm, - aluminium oxide, a-form, purity 99,9%, average grain size 80 nm.
The chromium powder was a commercial product of NewMet Koch, with the grain size ~40 µm and the purity of 99%.
After the sintering process, the ceramic powder create a uniform structure, independently on the previously used grain sizes.
The porosity is listed in Table 1 and the number of microcracks was calculated using the following condition (Equation 2): -σp ≤ σi ≤ σr (2) where σp and σr are the critical stress levels in compression and tension respectively, σi is the principal stress in ith direction.

For the longer etching time of samples in Fig.1 (c) comparing to Fig.1 (a), the grains are larger with continuous mountain shape in the whole surface of PS.
Fig.1 (b) presents a large number of grains with tubes-like, which can be considered as a self-assembly phenomena at the junction of grains.
As it can be seen from Fig.1 (d), the deposited Cu layer is formed along the peak-shaped nano-silicon grains on the PS surface.
Because the hemispherical grains with smooth surface are not high, and the distance between the hemispherical grains is very small (in nano-scale) in Fig.1 (a) , self-assembly Cu tubes in nano-scale are formed on these nanodefects and ragged sites when PS sample in Fig. 1 (b) is put into an aqueous solution containing Cu ions for 1 minute.
While as to the PS sample in Fig. 1 (c), many grains with peak-like shape are formed and Cu will deposite and distribute on the whole surface of such grains when it is put into the solution containing Cu ions.

It is attributed to that the grain growth of Ni particle has been constrained by modifying appropriate amount of ceria particle to reduce the obstruction of diffusion path of fuel gas and to enhance the amount of triple phase boundary (TPB).
Reduction velocity of hydrogen at TPB of anodes increases with increase of temperatures to generate more number of electrons, and therefore the logi0 values of anodes were enhanced.
It is due to that the grain growth of Ni particle has been constrained by adding ceria particle to suppress the obstruction of diffusion path of fuel gas.
Ceria could restrain grain growth of Ni at high operation temperatures to maintain smaller grain size and produce large amount of TPB in modified anode.
It is attributed to that re-arrangement and grain growth of Ni particle had been constrained by adding ceria particle to restrict the obstruction of diffusion path of fuel gas for enhancing amount of TPB.

Selected specimens were etched by picric acid in order to reveal prior austenite grain (PAG) size under optical microscope.
Prior austenite grains of the DQ offshore steel at (a) 7.5 mm and (b) 15 mm (center) below the water quenched surface.
Fig. 3 shows fraction of microstructure below the quenched surface simulated by JMatPro with the prior austenite grain size of 30 μm.
Fraction of microstructure below the quenched surface simulated by JMatPro with the prior austenite grain size of 30 μm.
Acknowledgements Authors gratefully acknowledge the financial support of this research by Ministry of Science and Technology, Taiwan (Contract number MOST 103-2622-E-006-037 and 104-2622-E-006-001).

There were 4-6 measurements in each sample and the average number was calculated.
Macrostructural studies at 50X magnification allowed to identify grain decrease in the «irradiated» metal.
Ferritic phase is in the shape of grid along the borders of pearlite grains.
The average size of grains in the «unirradiated» samples is 700 µm, in the «irradiated» with EMP samples is 450 µm.
Besides significant increase of the total length of grains boundary in the irradiated sample, ferritic phase is located continuously along all borders of pearlite grains.

In arc welding process, regardless heat treatment alloy or non-heat treatment alloy recovery, recrystallization and grain growth differences will take place in the HAZ regions.
In 7050 side is found to the microstructures point out, there are several layers to distribute of fine equiaxed grains, as shown in Fig. 1(a,b).
In post-welding by T4 treatment, the FZ and HAZ regions of the grain boundaries and its interior structure has distributed many fine black particles, as shown in Fig. 2 (a,b).
The two kinds of precipitates are uniformly distributed in the FZ and HAZ regions of grains and its interior structure [5].
In T4 treatment, the hardness value has dramatically enhanced in the FZ, PMZ and HAZ regions due to a large number of precipitations appear in grain boundaries and its internal structure.

It can be seen that when the working pressure was lower, the grain size was smaller too.
With the increase of working pressure, the grain size was getting bigger than that of before.
The agglomeration of grain at Fig.2(c) can be explained by that the activity of atoms which are sputtered from the target decrease with the increase of working pressure, and the areas of nucleation on the substrate will be narrow, and then there are areas with high energy, in which atoms will nucleate preferentially, and several grain nucleation will lead to agglomeration.
When the working pressure is more than 0.4Pa, the more the density of Ar+ was, the more the number of atoms sputtered from the substrate was too, though second impact with Ar+ is more likely to happen, there are also as many active atoms deposited on substrate, so it can not see agglomeration from Fig.2(c) and (d).
The increase of working pressure resulted in increase of the crystalline grain size.

It was observed that the grains of the ZnTe ceramic films were dense and uniform at a deposition temperature of 580oC.
The grain size and uniformity of the deposited film were enhanced and depend on deposition temperature.
Large grain boundary region is highly disordered, and having large number of defect states due to incomplete atomic bonding with lower deposition temperature.
These situations are known as trap states act as effective carrier traps, impeding the flow of majority charge carriers between the grains [10].
With increasing suitable deposition temperature at the growing film surface, the additional energy contributed to finer and uniform grain development in the ZnTe films.