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The polished specimens were also anodized at room temperature for 2 min using HBF4 to reveal the grain structure.
Results and discussion As seen from Fig. 1, all three materials exhibit an equi-axed grain structure.
Approximately 1000 grains were measured using the linear intercept method.
Figure 1 Grain structure of cast and homogenized, extruded and rolled materials (from left to right).
It is apparent that the size and number density of the constituent particles influence the size and density of the dimples.

The numbers of input and output nodes were determined by the numbers of input and output elements respectively.
Parameters such as the learning rate, number of hidden layers, and number of neurons in the hidden layer were used in the sensitivity studies.
Macleod, Prediction of directional grain size distribution: An integrated approach.
Oluyemi, Intelligent Grain Size Profiling Using Neural Network and Application to Sanding Potential Prediction in Real Time.
Faga, Formation-grain-size prediction whilst drilling: A key factor in intelligent sand control completions.

The strength calculation of cement and sand mixture, according to mentioned fracture criterion, was performed at the level of fine grain concrete model, wherein sand grains with size of 1.0-5.0 mm and pores with diameter of 0.8-2.0 mm in diameter are reflected.
Areas of the contact zone to the left and to the right from sand grains are characterized by the lowest level of stresses.
It should be noted that element deactivation represents multiplication of its rigidity matrix by small number (10-11), but not its physical removal from the model.
Figure 1 – Initiation of defects in concrete structure at the load level of 0.7×Pfract (filler grains are marked by white colour).
Repetitive loading of samples with maximum load — 0.7 Pfract, number of cycles — 100.

The SR is determined mainly by the grain size of PCD.
With the increase of the open circuit voltage, the force used to dislodge diamond grains from the matrix increases.
So the surface roughness of PCD blank after EDG is mainly determined by the grain size of the PCD.
This is because the number of pulse per minute reduces with the increase of pulse on time, and the wheel wear occurs in the rising edge of each pulse.
The SR is affected mainly by the grain size of PCD.

In addition to the discoloration, there was precipitation of a second phase at the grain boundaries of the resolidified Zr metal.
The second phase at the grain boundaries was rich in yttrium and oxygen which came from the dissolution of the yttria by liquid zirconium and Spot Number (see Fig. 7) Element 1 2 3 4 5 Oxygen 10.0 100 10 96.0 9.0 Zirconium 90.0 --- 90 4.0 91.0 (a) (b) 100 µm 10 µm Fig. 8.
then it segregated to the grain boundaries on cooling because of its limited solubility in α-Zr.
The dark phase at the grain boundaries contained yttrium, zirconium and oxygen.
Both yttrium and oxygen dissolved in the liquid Zr, but segregated to the grain boundaries on solidification. 5.

Due to the high number of publications on TCO for PV applications, this contribution does not claim to be exhaustive but makes it possible to summarize the main information concerning these materials by approaching them in a common methodology.
This small variation might be the result of the growing number of oxygen vacancies under increased substrate temperatures.
The increase in mobility (Fig. 2.b) for temperatures above 250 °C is attributed to the higher degree of crystallinity resulting in less grain boundary scattering.
ZnO having a high grain density and porosity, thus makes it possible to easily manufacture very sensitive gas sensors.
Table 4 shows a number of deposition techniques that are usable for ZnO based thin film growth and their features.

Figure 9 An example illustrating heterogeneous grain boundary ordering by a discontinuous grain boundary reaction in the Ni-Mo alloy after 100 hours of thermal aging at 700 oC.
Although the predominant fracture mode was intergranular, dimples were observed at separated grain facets indicating that fracture was preceded by highly localized deformation alongside grain boundaries.
(a) Auger spectrum derived from a freshly exposed grain boundary.
(c) An EELS spectrum representative of both the matrix and grain boundary.
This has been demonstrated for a number of alloys based upon the Ni-Mo system, which undergo long-range ordering reactions whereby the parent fcc lattice is transformed into nanoscale D1a or Pt2Mo-type superlattice depending upon the chemical composition.

Marine propeller blade is composition of complex rational space surface, most of its processing method is that milling is carried out first, and then uses a large number of artificial grinding to complete[1,2].
In Fig.4, the wear capacity of the ceramic grains belt SK750X is less than other two kind of belt, the second is zirconia alumina abrasive grains belt ZK713X, and the wear capacity of alumina grain belt is more.
The impact of abrasive grain type on material removal rate.
The new belt should be disposed properly when semi-finishing and finishing for marine propeller blade.the life-span of the ceramic grains belt is longer than the other two kind of belt, the second is zirconia abrasive grain, and the life-span of alumina grain belt is less.
The second is zirconia abrasive grains belt, and the material removal rate of alumina grain belt is minimum.

Grain size has an apparent influence on deformation mechanism of magnesium alloys[10].
In addition, fine grain in magnesium alloy may result in grain boundary slipping (GBS) to change grain orientation at room temperature, which has effects on the type and intensity of texture.
The as-extruded Mg-5Sn-xZn alloys show a typical equiaxed grain structure by dynamic recrystallization during hot extrusion, as shown in Fig. 1, the as-extruded microstructure is composed of coarse unrecrystallized grains and finer dynamically recrystallized grains, and new fine grains are nucleated on the boundaries of original grains and distributed around the large size (about 2μm) second phase.
It can be seen that these precipitates are distributed mostly within the recrystallized grains and rarely on the recrystallized grain boundaries.
The high elongation may be related to the fine homogeneous grains owing to dynamic recrystallization during hot rolling, fine grains may result in grain boundary slipping (GBS) to change grain orientation, meanwhile, the lattice reorientation caused by the tensile twinning is beneficial for further slip and contributes to increase the ductility [21], the addition of Zn to the Mg-Sn alloys can refine and increase the number of Mg2Sn precipitates, the effect of participate strengthening of massive Mg2Sn phase on the ductility of Mg-5Sn-3Zn alloy is obvious, so the strength and elongation increase slightly.

Under the high intensive pulsed magnetic field, the Al-Cu eutectic solidified morphology experience three evolution stages that are regular columnar structure to breaking off fine grain, coarsening dendrite to newly regularization columnar structure with increasing of 0～15.5J charge energy.
Introduction Pulsed magnetic field and electric current field have been widely used to control and modify the solidification process to obtain fine as-cast grain size, such as pulse electric discharging (PED) and electromagnetic stirring "Rheocasting process"[1].
Secondly, the grain size is not continues reducing with the increasing of magnetic field strength instead of coarsening dendritic structure at the higher pulse discharging energy, as seen by comparing specimen #2 (Fig.2 c, d) with specimen #3(Fig.2 e, f).
The rich copper phase enriched on grain boundary under instantly high-pulsed magnetic field, which may be related to the difference of electrdynamic potential between inner-grain and inter-grain.
The morphologies change from original regular columnar structure, fine grain of breaking off dendrite, coarsening dendrite structure, and finally to renewedly regularization of columnar structure.