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A number of techniques have been employed to synthesize this material in thin film and ceramic forms [2].
Grain size was obtained from SEM micrographs using direct measurement of grain length across the center of each grain.
This reduction in preferred grain orientation seems to be associated with the decrease in grain size.
Observed grain size reduction behavior can be explained by solute drag effect of La2O3 dopant on the grain boundaries of BIT ceramics which reduced diffusion rate and excessive grain growth.
Grain size was found to decrease with increasing La doping content which partly contributed to grain packing and orientation observed.

In recent decades, severe plastic deformation processes have been developed to achieve this grain refinement.
Compressive torsion with various numbers of revolutions was applied to Al–Fe alloys at 373 K.
Five test pieces were machined and numbered (1) to (5) sequentially from the center outward, as shown in Fig. 2.
Thomson, Ultra-grained Al-5 wt.% Fe alloy processed by ECAP with backpressure, Mater.
Kanetake, Refinement of grains and second phases in aluminum alloys by compressive torsion processing, Steel Int.

Although the grain was refined, the formability was depressed.
The random texture was possibly attributed to the decrease in c/a value, critical resolved shear stress for non-basal slip and the increase of the numbers of shear bands [8, 9].
The average grain size of the alloy was measured via the linear intercept method.
It could be known that the original grains were elongated and a large number of deformation twins appear inside the original grains.
Many fine DRXed grains and deformation twins which surrounded by the DRXed grains were shown in Fig.3a.

However, a number of failure mechanisms ultimately limit final ductility and formability.
Its early application was primarily for production of specialty aerospace and niche automotive components in small numbers [3].
The data of Figure 3(a) clearly show the superplastic response of fine-grained AA5083 (d = 7 µm), which produces significantly larger tensile ductilities than do the coarser-grained AA5182 and A5754 materials.
As Z increases, the apparent trend is toward convergence of tensile ductilities between the fine-grained and coarse-grained 5000-series materials.
Figure 3(b) presents data from coarse-grained Al-Mg and Al-Mg-Mn materials.

Statistical method means the number of samples must be sufficient to ensure the accuracy of results. β grain size and α lamellar thickness of as-cast Ti-6Al-4V alloy with different plate thickness were analysised.
Its grain size is coarse because of crystallization (Fig. 2(a)).
After the above steps, each β grain area can be measured (Fig. 2 (f)), which can be converted into grain equivalent diameter.
(b) (a) (e) (d) (c) (f) Fig. 2 Primary β grain specitic treatment scheme, (a) Grain metallograph;(b) Grain boundary depiction; (c) Grayscale conversion; (d) Binarization; (e) Image enhancement; (f) result output β grain size of cast plates with different thickness was analyzed by above mentioned method.
Fig. 3 (b) shows the relationship between average grain size and cast plate thickness. βaverage grain size is obviously influenced by cast plate thickness.

It appears impossible for a sufficient number of abrasive grains to exist in the machining area.
As a result, abrasive grains are concentrated and fixed around the tool tip [7].
Therefore, such a concentric pattern indicates that the tool tip is pressed against the workpiece and a sufficient number of abrasive grains could not be concentrated around the tool tip.
In addition, such chain shapes appear to prevent abrasive grains from being supplied to the machining area.
With these locations, it is believed that the chain shapes of ER particles and abrasive grains would not prevent abrasive grains from being supplied, and the machining of high-aspect ratio micro holes appears to have been achieved.

It was shown [4] that an increase in the number of ECAP passes led to a considerable increase in the static strength properties of the AA5056 in comparison with its initial state.
(ii) The ECAP results in deformed microstructure consisting of UFG grains alternating with unrecrystallized regions of coarse initial grains (Figs. 1(b) and 1(c)).
The average size of the ultrafine grains was ~1.2μm, the volume fractions of the coarse- and UFG grains were ~0.3 and ~0.7, respectively.
The room temperature mechanical properties of similar Al–6Mg–Sc(–Zr) alloys with the grain size of about 10mm (the microcrystalline (MC) state) and with the grain size of the order of 100mm (the coarse grained (CG) state) [11,12] are also given in Table 1 for comparison.
Also a large number of secondary cracks are often observed in these local regions.

Voro++ provides a radical Voronoi tessellation starting from a randomly generated set of seed points whose number corresponds to the number of cells obtained.
The number of iterations is referred to as the Lloyd factor in the following.
Another 2D VE has been generated separately with the same number of grains per 3D VE length in each direction, Fig. 1(c).
Afterward, the number of grains that possess a specific volume fraction is depicted in histogram bins in Fig. 2.
(a) (b) (c) Fig. 2: Statistical overview of the number of grains versus their volume fraction for 3D sections and 2D volume elements (for 2D with a unit out-of-plane dimension assumption) generated separately and by means of sectioning 3D volume elements.

Austenite Grain Refinement in Direct Charging based Thermomechanical Processes J.
The lower total reduction with a lower number of passes introduces some additional complexities that need to be evaluated.
Although the average grain size is about 800 mm, a wide range of grain sizes is observed, with grains as large as 2500 mm.
The applied strain is higher than εc for grains smaller than 800 μm.
Prediction of the grains under DRX conditions in an as cast grain size distribution in a 0.05% Nb steel (pass conditions: 60% reduction, 1070ºC, 5 s-1).

Compared HE1/E-TMB with HE2/E-TMB, the results showed that although they formed smaller grain crystals instead of spherulites with bigger size and complete structure, the grain crystals size of the former were bigger.
As can be seen from fig. 3, with the increasing of elastomer content of HE1/E-TMB blends, the number of the crystals increased gradually, and the size of grain crystals decreased, which induced the extent of the refining of crystalline increased.
They strengthen the heterogeneous nucleation and inhibit the growing of crystals. therefore, the number of the crystals in the blends increased, and the size of grain crystals decreased, which enhanced the refining extent of crystal gradually.
Furthermore, with the content of butylbenzenne elastomer N increasing, the number of crystals increased and the size of grain crystals decreased, the refining extent of crystalline reamrkably increased.
When E-TMB had the same composition, with the increasing of elastomer content of HDPE/E-TMB blends, the number of crystals of the blends increased and the size of grain crystals decreased, the refining extent of crystalline remarkably increased.