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Here, this technique has been utilized for microtexture determination, phase identification and misorientation distribution of grains and grain boundary of α-phase only.
This was estimated by providing a criterion for the grain boundary (misorientation exceeding 15o) and then isolating the grains.
From such isolated grains, misorientation between neighboring points of a grain was estimated and represented by GAM.
This provides a scalar number that describes the misorientation within a grain.
Recrystallized grains commonly have a lower value of GAM as compared to that of deformed grains [7].

The alloy pig is melting in the crucible oven（model number DRZ-12）by ohmic heating.
The eutectic Si was uneven and aggregative at the grain boundary.
The worse thing was seriously clustered at the grain boundary.
Not only the grain increased but also the size of eutectic Si largened.
They were aggregated into the grain boundary.

When the compression amount increases, the grains are crushed into small grains in size and exhibit chain distribution along the deform direction (Fig. 6b).
With increasing number of spinning pass, the compression amount increases and the microstructure are refined notably as shown in Fig. 8e.
Most of the initial grains of TA1, which are equiaxed in shape and about 10μm in size, transform into small and uniform equiaxed grains when spinning deformation degree reaches 0.8 (Fig. 8f).
However, there are still some elongated strip grains distributing among the equiaxed fine grains after hot plane compression (Fig. 8c).
When the deformation degree reaches 0.8, the original big grains are refined to about 3.5μm in size and uniform equiaxed complete recrystallization grains as shown in Fig. 10c.

The grains of ferritic matrix have a homogeneous distribution (uniform average grain size 41μm) and polygonal, equiaxed morphology with aspect ratio approximately equal to 1.
HAZ in TIG welding is consisted by non equiaxed coarsed ferritic grains (the average grain size is 90μm) which are characterized by partitioning of C, Si.
A critical and severe deviation to the average grain size is detected.
HAZ in Plasma is consisted by non-equiaxed coarsed ferritic grains (small deviation to the average grain size which 115μm) which are characterized by inhomogeneous distribution of C, Si.
The number of pulses above a given potential threshold (COUNTS) is related to the Barkhausen jumps in the area of the measurement [5-15].

Along with the original chemical crosslink points, these crystalline grains made the network more closely, and this induced a good reinforcement effect of the materials5.
In order to study the role of grain number to the stress at the condition of different extension ratios, Eq. 1 was used to calculate the crystallinity number index CNI.
(1) Where CI is crystallinity index; CNI is crystallization number index; B = 0.89; θ is Bragg diffraction angle; λ is the wavelength; β is half-width of the diffraction peak; k’ is a constant.
In the process of stress-induced crystallization, the nucleation increased, grains grew up and the crystallinity increased gradually.
The stress-induced crystallization occurred alone with the extension ratio when it was greater than 4.5, and the number of crystalline area grew more, the crystalline grains grew larger.

Calculated applied G number at the head toward centrifugal direction was 35.7 G.
a) and c): area analysis, and b) and d): point analysis inside primary Al grain.
Another is spot analysis aimed solute Si inside of primary Al grain.
Within the diamond powder densely dispersed region up to 3 mm, it seems number of diamond powder increased with approaching to the head.
On the other hand, grain size a) b) Fig. 7 a) The counts and b) grain size distribution of diamond powder in Cu/diamond FGM.

The melting Cu-enriched phase flowed to the oxidation surface along the grain boundaries of the oxide layer.
With a large number of fine holes distributed inside, the inner oxide layer of the specimens heated to 1300°C is less dense than that at 1000°C and 1100°C.
The oxide in the outer oxide layer has a columnar grain structure, and the composition of the columnar grains is Ti: 34.6%, O: 65.4%, Cu: 0%.
At this moment, the compositions of the grain and the Cu-enriched at the grain boundaries are Ti: 31.2%, O: 68.8%, Cu: 0% and Ti: 14.8%, O: 73.7%, and Cu: 11.5%, respectively.
The Cu-rich phase is not found at the grain boundaries of pure Ti oxide.

The orientations of the dynamic recrystallized grains with equiaxed shape were investigated by EBSD technique.
AZ61B is a common commercial magnesium alloy, the normal hot extrusion method can refine the grains and improve its mechanical properties.
Compared with as-cast structure, the grains is obviously refined, a great deal of equiaxed crystal was found, and the microstructure were ameliorated.
At the same time, mix crystal was found after hot compression, there are some grains that are elongated and the grains which have not taken place dynamic recrystallization
(3)Compared with the original grains, the as-deformed grains were obviously refined.

SPS method is more preferable as it results in less grain growth during compaction and larger reduction of .
Here the grains are modeled as particles made of two truncated cones with the common base.
So at such or smaller grain sizes the temperatures at the contacts have time to equalize with the temperatures inside the grains during the current pulse.
We have calculated also the dependence of dT on the number of particles up to Nnp=105 and have shown that the temperature difference dT virtually does not change when the number of particles is greater than 10.
The noticeable overheating for the bismuth telluride samples occurred only for the grain size larger than 50um, and the smaller grains in such conditions of SPS sintering are heated as a whole.

By using automated-parametric geometry creation the size, number and height of the individual bricks and joints can be varied.
Other microstructural techniques exist which explicitly model the topology and network connectivity of evolving grains and sub-grain structures.
For existing materials, experimental work is required to determine microstructure, measure grain size, grain distribution, grain boundary location and grain chemical content.
Under compression the grain facets are in contact and transmit the load, whereas in tension the grains are separated and the glassy matrix transmits the loads.
In this example, the fibre volume fraction, fibre spacing, fibre overlap, fibre angles in the different layers and the number of layers are controlled by parameters that can be easily varied.