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Seepage problem is of great importance to the stability of the soil dams in deep overburden foundation which is composed of coarse-grained soils.
Despite of that, grain composition is acknowledged as a crucial factor to the determination of engineering properties of coarse-grained soils[1-2].
Guo[1-2] studied the relationship between the hydraulic conductivities and content of coarse materials for 116 coarse-grained soil samples composed of sand gravels or loam with artificial mixed gravels.
Engineering properties and application of coarse-grained soils.
Permeability and seepage law of coarse grained soil.

Analysis of Crack Propagation Behavior in Alumina with Different Grain Sizes Under Static and Cyclic Fatigue H.
Crack propagation in high purity alumina ceramics with different grain sizes was investigated with the Double Torsion method during static and cyclic fatigue.
At low loads, the crack growth rate is initially equal to zero, but crack bridging decreases monotonically with the number of cycles.
Crack bridging in coarse-grained AKP19 alumina Crack bridging degradation under cyclic loading.
Thus, the compliance function could be monitored first as a function of the number of cycles, without any crack propagation.

Since a number of breaking of riveting ship and welding bridge in the early 20th century, the limitations of some impurity elements are included into the steel welding performance indicators.
The segregation of Sn in the grain boundary reduces surface free energy, weakens the binding force between the grains, and hinders the migration of grain boundary and recrystallization.
At the same time, considering that the atomic number and atomic radium have more effect than undercooling, the solute migration to grain boundary will affected by the barrier during the columnar crystal developing to the ingot core in the process of crystallization.
According to the study, the grain size relates to the segregation of Sn, which hinders the grain growth.
Grain boundaries in Metals, Oxford Univ.

The scan step was chosen so as to cover sufficient number of data points across the Cu lines.
Thus, as soon as the yielding begins the {111}<112> grains will grow faster in 0.18 µm lines because these grains will easily relax the stresses after yielding and the system will hence favor their growth.
If the average misorientation between the subgrains of the grain was at the lower end of the range 2-7o then the grain was classified as recrystallized or with lower dislocation density.
But it should be noted that the results are derived from EBSD investigation which only scans a limited number of (111) grains.
Secondly we are looking at only specific specie of grains i.e. only {111}<110> or {111}<112> and hence their number will obviously be even lower.

According to the SEM observation, the second phase of TiB2 and SiC particles synthesized in situ sited along the grain boundaries of B4C, meanwhile, those SiC particles of nanoscale size embedded into the B4C grains, and thereby, intra/inter-type ceramics formed.
The average grain size of B4C and Si powders were measured to be 1.5 μm and 4.0 μm, respectively.
Combined with the phase composition of BST samples, it is believed that the grains of smaller size and irregular shape stand for SiC, while the grains of larger size and rod-like shape stand for TiB2.
Smaller SiC particles of nanoscale size on the surface of B4C particles were trapped into B4C grains, and larger grains such as SiC and TiB2 resident along the grain boundaries of B4C, which form intergranular/intragranular structure.
Hejna, Abnormal grain growth and microcracking in boron carbide, J.

Surface development and parameter influence through cup forming A number of different tool tip radii and the resulting surface textures are illustrated in Fig. 3.1  4  5.
The grain structure in area A is only subject to a temperature load during the forming process without a change in the grain size.
In area 1, the direction of the elongated grains was changed by the forming process and a further stretching of the grains is realized.
Here, the grain size is reduced to 25  75 µm.
Compared to the grain structure at point 2 in Fig. 4, it is clear that a higher hardness is attainable with a higher grain refinement.

Effect of BSF layer thickness on photovoltaic performance of Si0.9Ge0.1 cells with mean grain sizes of 50 mm in SiGe layer.
Influence of absorption layer thickness on performance of Si0.9Ge0.1 cells with grain sizes of 50 mm.
Influence of Ge percent content on performance of solar cells with mean grain sizes of 50 mm in SiGe layer.
The average grain sizes d in crystalline SiGe absorption layer can influence the HIT cells’ performance.
Affect of average grain sizes on the photovoltaic properties of Si0.9Ge0.1 HIT solar cells.

Si3N4 based ceramic inserts have an advantage of high strength and high toughness as a result of elongated β-Si3N4 grains in the microstructure.
Experimental Procedure In this study, α-β SiAlON ceramics containing 50 % α and 50 % β SiAlONs were designed using multi-cation dopants including CaO, Y2O3 and/or a rare earth metal with atomic number greater than 62 and a rare earth metal with atomic number equal or smaller than 62.
Microstructural characterisation Typical back-scattered SEM images of the final microstructures of MDA1 and MDA3 are given in Fig. 1 where various phases can be clearly distinguished due to sufficient atomic number contrast; the β-SiAlON grains (which contain no rare earth element) are dark and more needle like, whereas the α-SiAlON grains (which contain a small amount of rare earth element) are gray and more equiaxed, whilst rare earth rich grain boundary phase appears white.
The amount of grain boundary phase between SiAlON grains can be significantly reduced compared with that of the previously reported α-β SiAlON materials [2].
In addition, compared to Si3N4, higher hardness is achieved due to the existence of α-SiAlON grains in the microstructure.

This suggested looking for differences in the ferrite grains nucleated along the graphite particles.
In Fig. 5-a is plotted the correlation between the number of ferrite grains in contact with the graphite particles versus the circularity of these particles for the sample cooled at 20°C/min, where circularity is 4·p·A/P2, with A and P the particle's area and perimeter.
The number of grains is seen to increase when the circularity decreases.
The similarity of grain distribution at low and high cooling rates suggests the distribution of nucleation sites for ferrite along the graphite particles is not sensitive to cooling rate even though the actual number of nucleated grains is.
Figure 5 – a) correlation between number of ferrite grains in contact with graphite particles versus the circularity of these particles; b) correlation between ferrite grain size and circularity of the graphite particles.

The microstructures of the samples were observed on a ZEISS Axioskop2 optics microscope, and MIAPS (Micro-image Analysis & Process) image analyzing software was used to determine shape factor and equal-area-circle grain diameter of primary phase.
The microstructure consists of priority to rosette-like, and a part of particle-like grains with coarse size as the current frequency is 30Hz (stirring 5s), as shown in Fig. 1a.
Compared with the microstructure of A356 alloy prepared by LSPSES, there are no dendritic crystals in the microstructure of A356 alloy no matter how the current frequency is higher or lower, which consists of the rosette-like or more globular- like primary phase and the size of the grain is smaller than that of grain in the alloy without stirring, as shown in Fig.1.
These indicate that the slightly electromagnetic stirring applied to the melt during the low superheat pouring can increase the number of crystal nuclei during solidification of the alloy to have the grain become fine, and can improve morphology of primary phase to have the primary phase become more roundness.
A-30Hz for 5s, B-50Hz for 5s, C-30Hz for 10s, D-50Hz for 10s, E-without stirring Fig.3 The shape factor (a) and size (b) of primary phase in the A356 alloy for the different preparing conditions Thus it can be seen that the suitable frequency conversion is applied to the melt prepared by low superheat pouring and slightly electromagnetic stirring is favorable to increasing the number of crystal nuclei and to fining the grain size to promote the formation of non-dendtritic grain so that the semisolid A356 slurry satisfied rheo-forming can be obtained.