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A commercial Al-Mg-Si alloy (Al 6082) was deformed by Equal-Channel Angular Pressing (ECAP) to produce bulk ultrafine-grained microstructure.
Introduction Severe plastic deformation (SPD) techniques are generally applied for obtaining ultrafine-grained (UFG) microstructure in bulk metals and alloys [1].
The applied load increased from 120 to 180 kN with increasing the number of ECAP passes because of the strain hardening of the alloy.
Figure 3: The volume-weighted mean crystallite size (vol) and the dislocation density (ρ) as a function of the number of ECAP passes.
Figure 5: The measured yield stress vs. the values of σTaylor calculated by the Taylor model. 0 2 4 6 8 0 100 200 0 3 6 vol [nm] ρ [10 14 m -2 ] Number of ECAP passesSummary Equal-Channel Angular Pressing (ECAP) was successfully applied to produce ultrafine-grained microstructure in a commercial Al-Mg-Si alloy (Al 6082).

When rupture occurs, the catastrophe point is the corresponding number of stress cycle.
The grid density changes with the length of the square L, and the grid number n (L) is counted.
The grid covering number was counted for 9 different side lengths of grids in Figure 1 to Figure 3.
The micro-cracks due to local plastic deformation is thin and straight, no matter the initiation is due to slip bands, grain boundary and twin boundary cracks or the interface between the inclusions (or the second phase) and the substrate [7].
The crack fractal dimension under different stress cycle number Samples1 Samples 2 Samples 3 Stress cycle number(106) D R2 Stress cycle number(106) D R2 Stress cycle number(106) D 0.48 1.1242 0.9718 0.40 1.1376 0.9544 5.00 1.0620 0.66 1.1305 0.9566 0.60 1.0921 0.9481 6.00 1.0620 0.84 1.0849 0.976 0.80 1.088 0.9423 8.00 1.0620 0.90 1.0663 0.9898 1.00 1.0727 0.9968 10.00 1.0620 The relationship between number of stress cycles and the fractal dimension was fitted as D=-0.4647N2+0.4932N+1 with R2=0.992, using the least-squares method for sample 1 shown in Figure 8.

One of the effective ways to improve the quality of semi-finished products made from aluminum alloys is to eliminate the columnar and fan-shaped structure in them, refine the grain and achieve homogeneity, is modification and alloying.
Introduction Aluminum and its alloys in terms of production and consumption take the second place after steel, and the spheres of their consumption are constantly expanding and in a number of industries they are successfully replacing traditionally used materials [1, 2, 3].
This contributes to the refinement of modifying intermetallic compounds, an increase in their amount and the production of a fine-grained structure [21, 22].
The chemical composition of the heats of ligatures No. 2, No. 6, No. 9 Experiment number Alloy formation temperature, [°C] Alloy base The amount of B in the ligature, [%] 2 1000 Al 1.08 6 1000 Al 4.50 9 850 Al 2.77 Fig. 1.
The study of the microstructure showed significant changes in the structure of the grains (Figure 5).

Therefore, the free water is decreased and the grain-to-grain lubrication action is weakened, which augments the soft soil viscosity, all which is due to the excessive addition of clay.
Reversely, in the condition of the same the rate of water content, when the clay content decreases, the free water increases, the grain-to-grain lubrication action strengthens, the viscosity decreases, and the flowing power becomes well.
Furthermore, the grains distribute sparsely and combine loose, and the interactional chance decreases which debases the cohesion force.
When the clay reaches the content of definite magnitude, the more near the grain-to-grain distance, the more tightly the grain-to-grain combination, and the more the interactional chance, which increases the friction force, strengthens the flocculation and forms the reticular structure of flocculation with stiffness of definite magnitude, and augments the initial shear force. 3) The influencing mechanism of the rate of water content for the soft soil rheologic parameters can be come down to the influence for the free water and the grain-to-grain flocculation.
With the increasing of the rate of water content, the free water in soft soil increases, the viscosity minishes, and the flowing power strengthens; at the same time, the grain-to-grain distance increases and the grains combine loose, the interacting is weakened and the intial shear force falls with it.

A total number of 22 points lied in two diameters for each sample were selected for indentation (Fig. 3).
As mentioned earlier, the direct outcome of SPD is grain refinement.
Reduction of grain size in materials leads to an increase in volumetric density of grain boundaries.
In addition, applying severe deformation to the materials causes higher number of defects in the microstructure.
Furthermore, grain boundaries may act as a pathway for diffusion and enable hydrogen atoms to reach the grains faster.

The microstructure of the cast alloy consists of a-Mg phase matrix with precipitates of Mg12(Ndx,Gd1-x) phase at grain boundaries.
Results Microstructure of Elektron 21 alloy in as-cast condition and after solution treatment The microstructure of Elektron 21 consisted of primary solid solution α grains with precipitates of Mg12(Ndx,Gd1-x) intermetallic phase at grain boundaries (fig.1).
The microstructure now contained a small number of β precipitates inside grains and areas with planar faults - stacking faults (Fig.5a).

The SEM result indicated that the average particle size and average grain size increased with the increase of calcinations and sintering temperatures, respectively.
Densities of the sintered ceramics were measured by the Archimedes's method and the average grain size was determined by using a mean linear intercept method.
The results indicated that grain size tends to increase with increasing sintering temperature (Table 1).
The average grain size was discovered to be about 0.87, 0.93, 0.96, 5.40 and 7.12 µm for the samples sintered at 1200, 1250, 1300, 1350 and 1400, respectively.
The average particle size and average grain size was observed to increase at higher calcining and sintering temperature.

In the case of La2O3 addition, the formation of grain boundary coherency was remarkably increased, and the sintered density was increased with increasing La2O3 contents.
Average grain size was about 2 µm.
It is also shown that the coherency of grain boundary is remarkably increased with increasing La2O3 contents.
As La2O3 increased, the number of effective dipoles increased due to the coexistence of rhombohedral and tetragonal phases. 14.5 15.0 15.5 16.0 16.5 17.0 17.5 18.0 18.5 0.025 0.020 0.015 0.010 0.005 0 La2O3 addition [mol] I-d31I [pC/N] Fig. 5.
The coherency of grain boundary was remarkably increased, and the density was increased with increasing La2O3 contents.

At 2040 oC, Abnormal grain began to appear.
Pores were distributed not only inside grains but also at grain boundaries.
It was hard to figure out grains and grain boundaries from the fracture surface.
It suggests that Al8B4C7 or Al inside the grains may contribute to remove the pores inside grains at the high sintering temperature, and to enhance B4C grains growth.
The micrographs of Fig. 12 (a) and (b) are back-scattering micrographs, in which high atomic number element shows light color.

Cluster analysis showed the possibility of reduction of the number of sensors.
Several variables from one sensor signal are calculated and analyzed using chemometric methods to reduce the dimensions of the data or to reduce the number of sensors.
Raw materials Sample Shape Strains Glutinous rice Soybean A.sojae 1) B.subtilis2) A Control - - - - B A.S 40 60 0.5 0 C Grain A.S+B.S 40 60 0.5 0.5 D A.S 40 60 0.5 0 E Brick A.S+B.S 40 60 0.5 0.5 1) A.sojae(A.S) : Aspergillus sojae 2) B.subtilis(B.S) : Bacillus subtilis Table 3 Proximate composition [%, w/w] of kochujang.
Cluster analysis showed the possibility of reduction of the number of sensors.
Cluster analysis showed the possibility of reduction of the number of sensors.