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The original microstructure consisted of equiaxed grains with a mean grain size of 25 µm.
The microstructure consisted of equiaxed grains with a mean grain size of 36 µm.
To account for twin generations each orientation was checked to find the number of twin generations.
The fifth test awards the orientation with the smallest number of twin generations with one vote.
P is parent orientation and numbers are twin generations.

Fig. 2 shows that for copper powder with coarse grains, the silver content after coating is relatively high.
Figure 1 Effect of silver multiple ion concentration on silver content with different grain sizes Figure 2 Effect of silver multiple ion concentration on resistivity with different grain sizes Effects of dispersing agent content on the properties of ACCP.
In Fig 6b silver sediment is also granular and silver grains clearly increase in number.
The silver grains are, however, individual isolated grains rather than continuous and the copper powder base is clearly visible.
* This project has been financed by the Chinese Ministry of Education through the New Century Excellent Scholars Program with project number 20060018.

Abstract: The cyclic load number of aero-engine blade during its service life is very likely beyond 107, which is regarded as the conventional fatigue limit.
When the excited frequency is close to the blade’s natural frequency, as the result of resonance, the cyclic number of large load is increasing dramatically.
To obtain a higher number of cycles per time , Morgan and Milligan developed a new sevo-hydraulic machines working in the frequency range of 1000Hz[2].
We may also see many nonlinear grain boundaries are unclear, which indicates a high level of both internal stress and distortion of lattice.
At this stage there exists a lot of quasi-cleavage facet accompanying with a large number of secondary cracks.

Number of dendrites in each alloy have been evaluated on five micrographs taken with the magnification of ×50.
Number of dendrites per alloy has been evaluated according to the equation: n = ni + 0.5×ne + 0.25×nc, where n is the number of dendrites per image, ne is the number of dendrites touching only one edge of the image and nc is the number of dendrites touching two edges of the image.
Moreover these alloys contain globular particles in the interior of the grains (Fig. 3).
The globular particles found within the grain of the α-Mg solid solution are composed of aluminium and manganese (Fig.4, pt.3).
Globular particles of the Al8Mn5 phase are observed within the interior of the grain.

Below (and commonly tacitly supposed in literature, but not explicitly mentioned) always only very large (infinite) macroscopic systems are considered containing a great number of grains, sufficient to represent an infinite system.
But, what is physically important: all grains are hard-wired with each other.
By example (8) and the numbers for{C}2 and {S}2-1 we can deduce {C} ≈ SQRT(C V · C R) = (4 · 10/3)1/2 = 3.651 .
As it has to be, for space-fixed grains (KЄ║KA) and fixed orientation of the crystal lattice in all grains (KB║KЄ║KA) (19) will describe at the end a single crystal, independently on {a1,a2,a3}.
The matrix can represent polyphase mixtures without pronounced grain forms.

Figure 1(a) shows the trace of a rotary diamond dresser on which a number of diamond grains or logs are arranged at the same interval.
This is because the time interval between the contact termination of a diamond grain and the contact start of the next diamond grain is so long that the grinding quill rotates several times without contacting the rotary diamond dresser and results in the nondressed part.
The trace depicted in Fig. 1(b) is an example of a dressing simulation using another type of rotary diamond dresser on whose surface a large number of diamond grains are distributed at random.
One of the discrete-type diamond dressers is a brazed diamond dresser (SL60) on whose circumference 60 pieces of single-crystal diamond are embedded at the same interval, and the other is a metal-bonded diamond dresser (MB270) on whose surface layer diamond grains of 270 in mesh number are impregnated at a concentration of 100.
In the case of the metal-bonded diamond dresser (MB270), diamond abrasive grains of which the nominal diameter is 50 µm protrude from the metal bond matrix.

affected zone is more fine, most lie in the grain boundary.
While air cooling, silicon particles in heat-mechanical affected zone distribute diffusely. the microstructure of heat affected zone is showing in Fig 1e, f , From figure , the grain size of heat affected zone is much more thin , which is half of air cooling welded joint, and the amount of Al-Si eutectic is smaller than air cooling welded joint.
Tensile strength about forced cooling by using liquid nitrogen and air cooling welded joint is showing in Table 2, welded joint grains fracture in heat affected zone.
Table 2 Strength of ZL114A friction stir welded joint Sample number Tensile strength (Mpa) Colling condition Average tensile strength (Mpa) 1 184 Air cooling 187 2 183 3 193 4 210 Forced cooling 212 5 213 6 213 Summary ZL114A was joined by friction stir welding and liquid nitrogen was used to cool the welded joint ,the amount of silicon particles in weld nugget zone is more larger and the size is more homogeneous。
the grain size of heat affected zone is half of air cooling welded joint and the amount of Al-Si eutectic is smaller.

Upper and lower bounds are given by Taylor [4], equal strain for all grains, and Sachs [5], equal stress for all grains.
Constitutive models, either phenomenological or physics-based, are required to determine the behavior inside the grains.
The model consists of a representative volume element (RVE) containing a large number of crystal grains with random orientations.
The number of grains is large enough so that the macroscopic flow curve is identical independent of the initial orientations of the grains.
A model developed by Ekh et al. [13] was adopted to describe the material behavior inside the grains.

As the microstructure of the absorber layer, especially grain structure, grain orientation, grain boundaries and their electronic behavior affect the device performance, we investigate CIGS absorber layers with a transmission electron microscope (TEM) equipped with a cathodoluminescence (CL) spectrometer.
The left grain in the CL mapping (Fig 4d) which is almost black in the CL image, consists of several smaller grains containing dislocations (Fig. 4c) The standard sample has a similar number of structural defects as the NaF precursor sample (Fig. 4e), but the contrasts at the grain boundaries are even less pronounced (Fig. 4f).
The dark lines along grain boundaries are very wide.
The Na containing films exhibit a comparably smaller number of these extended defects.
Grain boundaries and stacking faults act as nonradiative recombination centers.

The concentration of iron ions and aluminium ions in exudates is detected with inductively coupled plasma atomic emission spectrometer(ICP-AES) after numbering and processing according to rules for the whole infiltration solution which is collected in the process of the infiltration tests.
The data of concentration of ions and results of analysis on grain size gradations are shown in Fig.1 and Fig.2.
Furthermore, structural unit body of soil samples is decomposed into smaller grains as losing its viscous substance that could be carried away with seepage flow and finally make grain size gradations of soil samples unbalanced.
When “grain corrosion” has a leading function, the remaining coarse particles increase and the maximum pore size gets bigger.
Anyway, no matter it is in the process of “grain corrosion” or “grain decomposition”, the apparent porosity of soil samples shows an obvious upward tendency as the concentration of HCl in the solution increases.