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Deformation bands were observed in all grains.
The extent of deformation banding varied from grain to grain in terms of morphology and spacing.
The Vickers hardness number (VHN) was determined with a 300-g load.
Note the differences in terms of grain subdivision in adjacent grains.
Curling of grains is necessary to accommodate the flow of individual grains in bcc metals [10].

In some grains two twin variants were observed.
Inspection of the grain orientations reveals that some grains are in fact fully re-oriented by twinning after a compression of 10%.
Examples are given for two grains in Table 1.
Analysis of a larger number of grains is therefore currently underway to see if these observations also apply to the deformation of AZ31.
In some cases grains are fully twinned.

The insertion of SrTiO3 interlayer yielded BaTiO3 thick films with homogeneous and dense grain structure with the number of SrTiO3 layers.
There was no remarkable distortion in the BaTiO3 crystal structure for the thick films having various numbers of BaTiO3/SrTiO3 layers.
This suggests two phases coexisting in the film, and the ratio of the two phases can be artificially controlled by the number of coating.
A mixture of various grain sizes was evident for the BaTiO3/SrTiO3-7 heterolayered thick/thin films sintered at 1300 �, which showed very large grains coexist with very small ones.
It could be seen that the BaTiO3/SrTiO3-7 heterolayered thick/thin films with the number of coatings was also effective for increasing the grain size and improving the microstructure homogeneity.

The size of recrystallized grains having orientations of the rolling texture was considerably smaller than the size of grains having other crystallographic orientations.
Such grains were, on average, smaller than grains of other orientations (see Fig.4).
The largest average size was recorded for P- and CubeND-oriented grains.
The larger number of nucleation sites in the A6.4 sample resulted in a smaller average recrystallized grain size, 13 µm, compared to that in the recrystallized A3.6 sample, 19 µm (see Fig.4).
Once formed, P and CubeND grains were able to grow to a significantly larger average size than grains of other orientations (see Fig.4).

Initially low angle grain boundaries are formed and with further pressing the subgrains will transform into high angle grain boundaries with flow of dislocations into the grain boundary from within the grain.
Elongated grains could be observed after first pass.
As a result, large numbers of very fine precipitates are formed.
The grain size after ageing is 23μm.
Sample Condition Grain Size µm Hardness BHN 1.

An austenitic grain is considered (see Fig. 1, middle).
Within this grain, several martensitic variants, potentially all 24, may transform.
To homogenize the behaviour of 24 variants towards the response of the grain, the grain is virtually split in several domains.
The number and the volume fraction of these domains, is however, not known beforehand, but is obtained as the outcome of the transformation model on each of the potential variants.
The stress-strain responses of the transforming grain are also compared to the responses of the austenitic grain if no transformation would have occurred.

The irradiated pressure tube samples obtained from 13 locations were showing average alpha grain width, grain length and aspect ratio in the range of 0.17-0.27 micron, 1.7-2.3 micron and 7.1-8.5 respectively.
The off-cut from End-1 showed average alpha grain width, grain length and aspect ratio to be 0.18 mm, 1.65 mm, and 7.75 respectively.
The off-cut sample from End-2 showed average alpha grain width, grain length and aspect ratio of 0.2 mm, 1.7 mm and 8.0 respectively.
Hydride platelets were also absent in the irradiated Zr-2.5%Nb pressure tube unlike the irradiated Zircaloy-2 pressure tube samples, which showed significant number of hydride platelets.
The b phase had globulised in large number of regions but remained at the a/a interface.

Grain refinement is a promising technique for improving the strength and ductility of metal materials due to the strong influence of grain size on the mechanical properties.
Some twin crystals can be as long as 300um, which formed from the grain boundary, and finally at the grain boundary and many twins parallel to each other and with other twins stable at a certain angle range.
For large grains, stress concentration near the grain boundary is more obvious than the small grains, and thus a large number of twins and the volume fraction within the grains should be larger.
It is clear that annealing treatment also induces an unobvious grain growth in AZ31 alloy.
And with the increase of annealing temperature and time, the size of grains grows.

These types of steels often need to be added a large number of alloying elements, although the corrosion resistance can be improved, they have higher costs and it is not conducive to the promotion.
Some classical theories illuminated that the presence of grain boundary would block the dislocation movement, the grain was finer, the grain boundary was more, the block was more serious, and then the strength was higher.
For the whole substrate, there were a lot of segregation of impurities; the activity of the grain boundary was usually higher than that of the grain itself, so the grain boundary was prone to erode.
Compared to the coarse grain structure, the grain boundary area of the fine grain structure was much larger; therefore its activity of the substrate surface was higher, and its substrate was easier to erode.
From a thermodynamic point of view, the reaction free energy of the grain boundary was lower; the fine grain structure had more grain boundaries, so its surface reaction free energy was lower, and then it was easier to erode, as shown in the first corrosion cycle in Fig.4.

The next is that diamond grains are plated and then nickel is plated again.
If the feed load is permanent, the diamond grains density decreases and the depth of the diamond grains into granite increases as the diamond grain size increases.
Table 2 Effect of diamond grain size on slicing process Grain size [Mesh] 170～200 200～230 230～270 Cutting force [N] 3.25 2.99 2.81 Cutting efficiency [mm/min] 8.04 7.68 7.50 Effect of Wire Speed.
If the pressure is permanent, as the wire speed increases, the number of cutting diamond grains increases per second and the depth of the diamond grains into granite decreases.
The depth of the diamond grains into granite increases and cutting efficiency rises as the diamond grain size increases.