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The angle of 15° [26] was defined as transition between low-angle grain boundaries (LAGB) and high-angle grain boundaries (HAGB).
The confidence index of the grains was standardized and the EBSD data was then cleaned via grain dilation, considering the minimum confidence index of 0.1 and the minimum grain size of 5 µm.
The grain orientation spread (GOS) cube in Figure 1 (b) shows recrystallized grains with misorientation spread < 1° (blue).
Even though grain sizes and grain shapes are similar in RD and TD, they are quite different in ND.
Consideration of grain interaction and grain co-rotation to account for correlations between the orientations of neighboring grains may eventually improve the results of the performed simulation.

Fig. 3(a) shows a large number of original coarse grains are heavily elongated vertical to the deformation direction.
In addition, it is hard to find new recrystallized grains in the Fig. 3(a).
With the temperature increasing up to 550˚C, some new fine recrystallized grains have been formed at the grain boundaries and the elongated grains became obscure.
By increasing the temperature to 750˚C, the occurrence of dynamic recrystallization is clearly observed at the vicinity of grain boundaries and also in the grains interior.
And the original fibrous microstructure was completely replaced by fine, equiaxed recrystallized grains.

We find that the room temperature MR in the sputtered films depends on the trigonal-axis oriented microstructures and grain size, in contrast to the electroplated films.
Journal Title and Volume Number (to be inserted by the publisher) Fig. 3 presents scanning electron microscopy (SEM) images of (a) as-sputtered and (b) annealed Bi films.
The as-sputtered sample shows submicron-sized grains, which is much smaller than the trigonal-axis oriented grains in the annealed sample.
This supports the view that grain boundary scattering mechanism is dominant in the MR response at room temperature and that the very low MR ratio in the as-sputtered sample is attributed to the small grains.
We also found that the room temperature MR for the sputtered films largely depends on the trigonal-axis oriented microstructures and grain size, whereas that for the electroplated films is almost independent of them.

The austenite grains are fully refined after sufficient rolling pass and finally basically the same fine-grained ferrite grains (about 0.4mm) as niobium steel are obtained through controlled rolling, which is the grain refinement mechanism of vanadium steel through recrystallization during controlled rolling. 　　
As the strong affinity of nitrogen and vanadium, with the increase of nitrogen content in steel the number of V(CN) increases, the size and spacing of V(CN) precipitates significantly reduce.
Vanadium-nitrogen micro-alloying fully plays its role of grain refinement and precipitation strengthening by optimizing vanadium precipitation and refining the ferrite grain, which significantly improves the strength and toughness.
The ferrite grain size increases with the decrease of finish rolling temperature, so that it has higher strength and toughness
Higher nitrogen content increases supersaturation and nucleation rate of precipitates, thus promotes precipitation of large number of fine dispersive V(C,N). 　　

The experiment was divided into three testing areas with different numbers of reductions, different strain rates and forming temperatures.
Microstructures of the specimens were then examined for their grain sizes and volume fractions of phases.
Microstructure in the center of sample No.13 Summary Simulation of Rolling on a Plastometer A number of tests on the GLEEBLE plastometer simulating the rolling of vanadium microalloyed steel has been performed.
The grain size in the examined grade of steel shows no tendency for decreasing with decreasing temperature.
The ferrite grain size in the centre of specimens fluctuates around 8 according to ASTM E112.

It consists of thickened ferritic polyedrical grains whose dimensions range from 0,1 to 0,25 mm, The secondary austenite is created on the borders of ferritic polyedrical grains.
Number of measurements in the weld metal was dependent on the width of recast and ranged from 7 to 11 measurements.
Secondary austenite is formed on the border of ferritic grains, which grew up to the volume of ferritic grains in the form of needles.
In the volume of ferritic grains grew up austenite in the islands form, sometimes linked.
The dimensions of austenite grains in the recast resembled to the dimensions of austenite grains in the base material.

The main advantage of the dynamic channel pressing method (DCP) compared with the equal channel angular pressing ECAP is the substantial increase of productivity of the method by increasing the speed of pressing and reduction of the number of repeated passes through the channel of the die to achieve the desired uniform distribution of grain size in a specimen volume.
As a result, the grain grinding of the material structure in the deformed block occurs mainly in the middle of the specimen.
Acknowledgement The reported study was supported by the Ministry of Education and Science of the Russian Federation within the framework of state job number 2014/223 (project 1943) and RFBR within the scientific project № 14-01-31144 mol_a.
Tolmachev, Evolution of the temperature field during deformation and fracture of specimens of coarse-grained and ultrafine-grained titanium, Russian Journal of Nondestructive Testing. 47, 10 (2011) 701-706
Gurov, Dynamic deformation of titanium for producing ultrafine-grained structure, Proceeding of Intern. conference “Shock waves in condensed matter, High Pressure Centre, St.

The Weibull parameters “m” and so were determined using correction factors according to the number of samples used (DIN-51-110).
One of the ways to toughen the material is to reduce the average grain size, increasing the number of grains in unit area and hence the contours to be overcome by the crack during its propagation.
Thus, the material with finer grain microstructure of the crack may require more energy to keep growing.
This (s) grain (s) to suffer (in) stresses caused by the growth of a crack can become phase, turning into monoclinic ZrO2.
To obtain ZrO2 ceramics with high fracture toughness is required to produce blocks with grain refined microstructure and a high content of tetragonal phase.

Standard EBSD analysis can also be used to define grains and grain boundaries, and to locate other features such as twins [4].
Only a small number of attributes were used in the trials reported here, leading to uninspiring correlations in some cases.
The positions of tensile twins and their parent grains, as indicated by OIM software [4], were captured and fed into a machine learning environment, along with various attributes of the grains – including grain size, average measured strain (using high resolution EBSD - HREBSD) and the dislocation density components measured by HREBSD.
Predicted correlation between grain size (area in square microns; x-axis) and propensity for twin formation (y-axis) based upon AZ31 data (right).
These attributes included the grain size, the average size of neighboring grains, the average misorientation between a grain and its neighbors, the macroscopic strain and the maximum Schmidt factor for slip systems in the grain.

Specifically, no excess Sn4+ adsorption to the grain was observed, so the grain is not relatively dense, and dry film stress will not be too concentrated.
No excess reaction was observed in the alkaline solution, thereby indicating that the reaction of the driving force is not large, the process of generating the grains is slow, the formation of tin oxide grains is uniform and small, and small grain composition of the stress concentration is few.
This molar ratio is possibly appropriate to make the tin oxide film grain small.
Small grains lead to the formation of thin film, and the fine binding among the grains is good.
During the subsequent accumulation process, most of the grain accumulated to a certain height will collapse or too late to accumulate into a peak due to the unstable accumulation between large grains, so the number of peaks will be considerably reduced, a remarkable reduction in height was observed.