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The area fraction of small grains seems to increase with holding time, but the unrecrystallized grains and the recrystallized grains are not distinguished very clearly.
The elongated austenite grains have significant misorientation inside the grains.
Therefore, the small austenite grains are presumably recrystallized grains.
As indicated by the double arrows in the enlarged martensite orientation map, even the small α grain contains a number of variants.
Other small recrystallized austenite grains indicated by the single arrows also contains a number of variants.

The small equiaxial grains were not found at the bottom of the casting.
In Fig. 5, it could be found that the grain orientation was influenced by the seed-layer.
Because the inner part of Fig.5-(d) is the square, the grain control only occurred at the square area.
It supplied the optimum seeking direction to the dendrite and constrained the grain size.
Add the seed-layer could be observed the grain size enlarged and the grain number kept in equal.

The lower roller should be rotated with the degree of 180 / z, where z is the teeth number of the tooth-shaped roller, then the teeth of the upper roller and lower roller are matched correctly.
The teeth number of these tooth-shaped rollers is 18.
As can be seen from the Fig. 5 and Fig.6 can be seen in the relative reduction of 10%, P1 point and P2 point of grain grain changes little, about 1.2 um .
The relative reduction is 8%, the grain and P2 grain size change P1 point is small, it is about 1.25um Thus it can be seen that the relative pressure increases, the grain size decreases.
Increasing the rolling speed, the grain can be refined.

The major obstacle to the practical application of the alloys is the poor formability at room temperature, originating basically from the insufficient number of slip system.
The microstructure exhibits an inhomogeneously developed microstructure that consists of elongated coarse grains parallel to the extrusion direction and some large grains and small grains.
After 60% rolling, by CS and LS sample (Fig.3(e),(f)) twins are disappeared and small equi-axed DRX grains unlike by TS sample(Fig.3(d)), in which twins, large grains and small grains are presented.
The distribution of grain size is shown in Fig.4.
In the TS sample, twins, large grains and small grains were developed, as shown in Fig.3(d), while in the CS and LS sample, a homogeneous microstructure with smaller grain size was developed, as shown in Fig.3(e),(f).

Therefor it is necessary to construct a large number of long distance pipelines from remote regions to consumption areas [1].
According to the distance to the subsequent bead, the weld metal of whole filling pass can be divided into coarse grain zone (CGHAZ), fine grain zone (FGHAZ), critical reheat coarse grain zone (IRCGHAZ), as shown in Fig.3.
G can be used to describe the grain size.
And the smaller the value of G, the bigger the grain size.
(2) (3) Where L is the straight length adopted by intercept method (mm), N is the number of the grains intercepted by the straight, and M is magnification of microscope.

The depth of deformation zone was almost same as that of the peak damage region Deformed area Median crack extension A number of dislocations and strain contrasts at outer deformed area 1000 nm 2000 nm 3000 nm Dislocation growth Grain boundary Indent No change of crack extension direction at grain boundary Deformed area Median crack extension A number of dislocations and strain contrasts at outer deformed area 1000 nm 2000 nm 3000 nm Dislocation growth Grain boundary IndentIndent No change of crack extension direction at grain boundary No dislocation in the damaged region Deformed Area Strain bands A zone of irradiation peak 1000 nm 2000 nm 3000 nm IndentIndent (b) Dual-ion, 1 dpa, 800 °C (a) Unirradiated SiC Deformed area Median crack extension A number of dislocations and strain contrasts at outer deformed area 1000 nm 2000 nm 3000 nm Dislocation growth Grain boundary Indent No change of crack extension direction at grain boundary
A number of indentation-induced dislocations were exhibited from the boundary of deformation zone and matrix, and distributed widely in the matrix.
One possible explanation for crack tilting along the grain boundary is coalescence of point defects on the site of grain boundary.
The grain boundary becomes an unstable region.
and grain boundary may cause this crack extension along grain boundary under compressive stress because of an easy formation of microcracks along grain boundary.

Experimental results indicated that for the single layered films deposited directly on substrates at Ts = 300 ℃ and Ts = 500 ℃, most of the grains are acicular type grains with their c-axis in-plane and/or randomly oriented.
For the single layered BaM thin film deposited at Ts = 300 ℃, both the elongated acicular grains and platelet-like grains are observed (see Fig. 4a), the elongated acicular grains fuse each other and occupy a much lager area than the platelet grains.
Previous studies have confirmed that the elongated acicular grains are in-plane and/or randomly oriented, while the platelet-like grains are c-axis perpendicularly oriented [4, 5].
However, by introducing the 20 nm thick BaM layer acting as interfacial buffer layer, the number of perpendicularly oriented nucleation sites is significantly increased, and the stress and dislocation extending from the film-substrate interface are released.
Thus, the growth of platelet-like grains is significantly enhanced.

The bo grains exhibit complex shapes, while the morphology of the a2 grains is hard to determine since hardly any grain boundaries are visible.
During the period in which deformation was stopped, the number of parallel timelines observed is higher than the one before deformation, which is indicative of grain refinement.
Additionally, the number of dots increases.
During deformation, the AT plot shows a number of inclined timelines which are visible for several tens of seconds.
Upon deformation, the number of dots increases which indicates grain refinement.

Introduction The physically-based models of bainite transformation deal so far with transformation kinetics [1,2] or at best with a grain size estimated from the number of nucleation events [3].
These two austenite conditions will be referred to as fine-grain and coarse-grain in what follows.
Misorientation angle distribution obtained for different cooling conditions: (a) coarse-grain austenite, (b) fine-grain austenite.
However its extent strongly depends on the austenite grain size: for coarse-grain austenite only slight reduction is observed whereas for fine-grain case the packet refinement has radical character.
Length fraction of inter-variant boundaries for bainite formed in (a) the coarse-grain and (b) fine-grain austenite at various cooling conditions.

The calculations indicate that increasing the alignment degree of the grains, the coercivity increases.
However, Gaussian or f(a) = cosn (a) assume small number of misaligned grains.
The main objective of this article is testing Person VII for texture description, because this function can include misaligned grains in larger number than other distributions as Gaussian or f(a) = cosn (a).
The main advantage of the Pearson VII distribution [6] is the inclusion of the effect of misaligned grains, which may be found by EBSD analysis [2,7]
The Pearson VII distribution maybe more adequate for describing texture when misaligned grains are present.