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However, the coercivity of the former is higher due to its smaller grain size.
From it, it seems that the structures of both samples are dense, and their grains are of uniformity with no abnormal grain growth.
Larger grains tend to consist of a greater number of domain walls.
As the number of walls increase with grain size, the contribution to magnetization or demagnetization due to wall movement vis-a-vis that due to domain rotation increases [5].
The number of ferrous ions on the octahedral B sites plays a dominant role in the mechanism of conduction and dielectric polarization.

The CR 7075 Al alloy shows improved fracture toughness and tensile strength due to high dislocation density, grain refinement, and ultrafine-grain (UFG) formation by multiple cryorolling passes.
The microstructure of the bulk alloy exhibits lamellar grains having average grain size around 40m, lying parallel to the ingot axis.
Since the dynamic recovery is effectively suppressed by rolling at cryogenic temperature (-190oC), the CR Al 7075 alloy shows high amount of dislocation cells and ultrafine grains or grain fragments.
(1) Where, = Constant (Mpa m1/2), d= Grain size.
Dislocation piled up in the grain boundary, during cryorolling, rearrange themselves, and form sub grains.

Non-destructive technique based of X-Ray Diffraction Contrast Tomography also exists [6] but presents some limitations regarding the materials and/or the number of investigated grains.
Figure 3: Grain size distibution of 75 grains with transgranular cracks and of 815 grains without crack.
This crack may have been slowed down by grain boundaries (between grains 38 and 46 in Fig. 2b).
The cracked grain has a complex morphology: it contains two elongated twins which do not cross the full grain in depth.
This individual grain appears as three distinct grains in 2D surface orientation map (grains 37, 44 and 46 in Fig. 2b).

The superplasticity observed in this studied condition may be attributed to mechanisms of dislocation creep mainly within large grains and grain boundary sliding (GBS) of small grains.
A small number of large grains of approximately 20 µm in diameter are embedded in a matrix of small-recrystallized grains about 5 µm in diameter.
The grain compatibility during grain boundary sliding is also required to maintain by some accommodation mechanisms [10].
Moreover, it is also well known that grain boundary sliding is usually considered as a major possible plastic deformation mechanism in fine grains materials, and dislocation activity in fine grains (less than 5μm) is presumably very limited [6].
The mechanisms for superplasticity in present alloy may be a combination of dislocation creep within large grains and GBS of small grains.

This will allow to save metal, reduce the required deformation force, costs of labour and energy due to reduced number of passes of the metal through the working stands.
That is, the use of this tool provides a fine-grained isotropic structure in the volume of deformed metal.
The maximum difference in the number of slip lines when comparing longitudinal and transverse cross sections is observed after rolling of brass billets in smooth rolls (fig. 5).
Visually, this is reflected in the fact that within some grains of the glide lines of dislocations more than the other (fig. 5 a,b).
After rolling in the relief rolls, this is not observed, the distribution of slip lines within individual grains and in the other direction is uniform (fig. 5 c,d), i.e. all the grain in a relatively equally involved in the gliding of the dislocations, and, consequently, in the plastic deformation.

For the highest values of stress gradient, the number of points in each bin tails off, leading to large variability.
Scatter plot of average value of KAM in each grain against the size of the grain (291 grains).
No correlation between misorientation and grain size is evident.
Lastly, in order to check whether the development of orientation gradients is related to the grain size, Fig. 6 shows the KAM averaged over all points in each individual grain, plotted against the size of that grain.
No relationship between orientation gradient and grain size was apparent, nor was any correlation with grain orientation found.

Dimensions of packets and blocks could not be determined with high accuracy due to the fact that a limited number of areas could be analyzed by careful orientation analysis [3].
Average size of these grains is ~2mm and, therefore, the 9%Cr steels are ultra-fine grained materials.
No remarkable changes in size and number of these carbides located along block boundaries were found.
This is caused by large Zener drag pressure on these HAGBs due to large number of the M23C6 carbides and Laves phase.
By contrast, minor normal grain growth occurs under creep.

However, as known form other materials, these properties are significantly influenced by the grain size [2,3,7,8] because during magnetization the movement of Bloch Walls is hindered at grain boundaries due to the change of the preferred direction of magnetization which is related to the grain orientation.
Average chemical composition, grain size and used temperature of recrystallization, TR.
The number of revolutions was chosen in such a way, that the von Mises equivalent strain gvM = 2rrn/(-3 t) [10] was 32 at a radius of 3 mm for all produced samples.
Thus, the captured micrographs depict the grain and subgrain morphology of the severely deformed microstructure because in a single phase material, the energy and intensity of BSEs (brightness) depends among other things (order number of elements, topography) on the orientation of the crystallites with respect to the direction of the incident electron beam.
Pippan, Proc. of Symp. of Ultrafine grained materials III, TMS (2004), p. 629-634

A number of offshore structure maintenance method require underwater working.
From the observation of metallographic microstructure underwater welding it appears that phase grains coarser than the microstructure of welding on land.
This can happen because the weld metal suffered liquefaction then freezes so quickly that opportunity grain experiencing severe grain growth during thawing did not get transformed into finer grains, so that the material is harder but brittle.
Weld metal run into liquefaction then freezes so quickly that opportunity grain growth could not be transformed into finer grains due to rapid cooling.
This is due to the austenite grain area owned by the biggest austenite grain.

Introduction A grinding wheel could be defined as a composite substance consisted of a large number of abrasive grains bonded together with the binder maintaining the specific porosity from 20% to 40%.
It plays a key part apart from abrasive grains.
,Si3O8] sanidine 2.38 7,60 <1000 As a result of combining the components [Tab.2], the composites marked with the following symbols were obtained: CD - grain of boron nitride + binder D CS - grain of boron nitride + binder S Table 2.
CBN abrasive grain bond CBN abrasive grain bond Fig.1.
bond CBN abrasive grain CBN abrasive grain bond Fig.2.