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In the presence of lutecium (a), the diametrical growth of the silicon nitride grain is faster than when lanthanum (b) is present, resulting in low aspect ratio grains.
Combined with the greater preference of La for residing at the silicon nitride grain surfaces, these can be taken as mechanisms for limiting diametrical grain growth resulting in high aspect ratio grains when La is one of the components of the sintering additives.
With increase in creep strain, one observes an increasing number of these elongated grains that either contain cracks or are fractured.
As a result diametrical grain growth is impeded and elongated grains, which are desired to toughen the ceramic, are formed.
Rühle, "Grain Boundary Films in Rare-Earth-Based Silicon Nitride," J.

Grinding process becomes very complex and difficult to analyze, because the distribution of abrasive grains is stochastic and abrasive grain geometrical shape is anomalistic.
Because the number of cutting points is large, cutting point geometrical shape is anomalistic, grinding velocity is high, every abrasive grain's cutting depth is small and inconsistent, especially the spark eject from grinding wheel, all of these make the process become elusory.
We know there are large numbers of cutting points whose geometrical shapes are inconsistent arrange irregularly on the surface of grinding wheel and their positions and directions are stochastic, So the cutting geometries of abrasive grains are different each other.
In order to make the simulation close to true grinding process, we should get a universal ubiety (abrasive grain 1 and 2. in Fig.2), the height of abrasive grain 1 is higher than the height of abrasive grain 2 and the abrasive grain 1 locate top left direction of the abrasive grain 2.
From Fig.5 we can see the area ABCE is cutting volume of abrasive grain 1 and the area BCD is cutting volume of abrasive grain 2.

The number of layers includes all metal and ceramic layers.
Ni grains form big aggregates and distribute among Al2O3 grains.
The Al2O3 grain size in Al2O3 sample is about 0.4-0.7µm.
The grain size of Al2O3 in the (Al2O3+20wt%Ni) and (Al2O3+50wt%Ni) is about 0.3-0.5µm and 0.4-0.6µm.
According to the Hell-Petch formula, the strength will increase as the grain size decreases.

The relatively large initial grain size permitted the identification of the fine DRX grains nucleated at the TJs of the original grains.
It is notable in Fig. 3 that TJ nucleation was already detectable at ε = 0.1 and that the number of new grains increased monotonically with strain.
In this strain range, no nucleation was observed either on grain boundaries or in the grain interiors.
Nature of grains nucleated The crystallographic orientations of the grains nucleated at the TJs at a strain of 0.2 were analyzed using OIM.
This revealed that more than 90% of the new grains had Σ3 relations with one of the surrounding grains, irrespective of the testing temperature.

The input layer has two nodes, respectively, deformation temperature and strain rate, the output layer also has two nodes, representing the recrystallized grain size and flow stress.
Literature[2] indicates that, the geometric mean can be used to select the processing unit the number of rules to the intermediate layer.
For the three networks, where the number of nerve cells between the hidden layer is selected by the following formula: （2） （3） In the formula, is the number of units in the hidden layer, is the number of units of the input layer, is the output layer unit, is the learning capacity of the sample, is a constant.
After the increase in the number of cells in the middle layer, network with fewer steps training can converge to a certain error range.
Figure 2 is the recrystallized grain size and the prediction error image training error.

The grain orientation texture and (grain) spatial distribution of, at minimum, 1 mm × 7 mm (RD × TD) EBSD maps of BR_HR and GR_A materials were compared.
This method reduces the total number of experimentally measured points to a set of 2000 equally weighted orientations.
Only the {123} <634> S-oriented grains are shaded in Fig. 3(a) since they constitute the highest volume fraction of grains in the BR_HR material.
Fig. 3(e) shows that the IA resulted in elongated, coarse grains which have an average grain size (determined from line intercepts) of 129 µm (compared to a mean size of 100 µm for all non-Cube, 15° tolerance, grains) and a volume fraction of ∼51%.
Acknowledgment This research was carried out under the project number MC4.05238 in the framework of the Research Program of the Materials innovation institute M2i (www.m2i.nl), the former Netherlands Institute for Metals Research.

According to the initial grain size of 25 µm these measurements show, therefore, that ABE is effective in reducing the grain size of this Mg-based alloy.
The recorded grain sizes, however, were achieved by ECAP process after eight passes, where un-processed material possessed a grain size of 15~22 µm [9].
As the increase of strain, the size of fine grain is less affected by ABE passes, while the coarse grains are refined continuously by dynamic recrystallization [3].
Fig. 3 a) True stress versus true strain at room temperature for as-received and processed experimental alloy, b) Variation of the yield stress, UTS and tensile elongation with the number of ABE passes.
The more the number of passes the more pronounced hardening effect may be seen in the material.

Ensuring Strength of Fine Grained Concrete with Mixed Cement Binders A.
Yung it has been proven that hardened cement stone contains a large number of unreacted cement grains, which can be replaced without loss of strength with the corresponding fractions of mineral additives.
In modern construction, the use of fine-grained concrete (FGC) is due to its special properties compared to traditional heavy concrete.
Purpose of the Work Ensuring the strength of ordinary fine-grained concrete with the rational use of cement.
However, this indicator is equalized by the number of CASB with its maximum amount (х2=+1) in concrete 400 kg per 1m3.

The recrystallization microstructures consisted of equiaxed grains and a large number of the annealing twins.
Texture evolution during the recrystallization and grain growth.
Then, in the subsequent grain growth stage, the similar preferential growth occurs on the grains with the same orientation as the as-rolled texture since these grains can form the 40˚<111> GBs with the grains in the primary recrystallization texture.
However, they did not find the texture return by the grain growth.
Regarding the texture evolution by the subsequent grain growth, observed was the tendency that the {110} texture components appeared during the grain growth [17].

On the other hand, the number of research works as to SPD of commercial medium carbon steels is still limited, because SPD processing is relatively difficult in steels with higher flow stress.
Grains of pearlite with size of ~ 50 μm are lined by the finer ferrite grains (~10 μm in diameter).
These pearlite grains are lined by finer ferrite grains, Fig. 1a.
Finishing ECAP deformation the corresponding effective strain in dependence of number of passes was εef = 2.7, 3.4 and 4 respectively for individual samples.
The deformed microstructure, which resulted from different ECAP straining of steel, related to different number of passes through die channel 500 nm (N= 4 and N= 6 passes) is presented in Fig. 4.