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(a) Cluster of neighbouring grains with initial strong rotated cube orientation and (b) group of neighbouring grains with different initial orientations.
They concluded that the orientation splitting in a-fibre grains, resulting from a deformation banding process, produced the necessary lattice curvature for certain a-type grains to recrystallize at the expense of other a-components in the original grain.
Fig. 4 displays the IPF maps of grains with an initial rotated cube orientation (Fig. 4a) and grains with a-fibre orientations (Fig. 4b).
The detailed substructural characterization revealed the development of orientation gradients within grains with a rotated cube orientation or a-fibre grains.
Acknowledgements This research was carried out under the project number MC5.07294 in the framework of the Research Program of the Materials innovation institute M2i (www.m2i.nl).

In the course of annealing, these nuclei increase in their sizes, their number increases as well, and gradually they form continuous fine-grained layers.
In the dark-field images taken in the reflections of Nb and Nb3Sn the grains of the superconducting phase (upper right corner) are adjacent to the residual Nb densely populated with a large number of very fine (10-20 nm) nuclei of the Nb3Sn.
Compared to the previous sample, a greater number of second-phase particles are observed (indicated with arrows in Fig. 14c).
The number of these particles is not very great and not enough for the pinning force enhancement, but the Nb3Sn grains in the vicinity of these particles grow coarser.
Here, it is important to remember that wide zones of fine equiaxed grains are of great importance for high performance of the wires not only from the viewpoint of greater number or uniformly distributed pinning centers (grain boundaries).

This design is based on the structure of various thresher, the main research of the corn thresher drive system structure, working principle, and on this basis, based on the design of the finished parts, on corn dish itself characteristic to carry on the design, when threshing grain rod roller high-speed rotation, the corn by continual lines between grid type and gravure roller rod, and the action between the corn cob constantly collide with each other, to achieve the seed plate separation, then the net grains, complete threshing.
The function of it is for grain threshing. 1)The work principle of threshing device Based on the characteristics of the corn crop threshing and the corn thresher threshing device adopts the workings of a threshing.
Roller speed for corn thresher. 2)The type of threshing device The corn thresher threshing device is the type of movement types are tangent type, threshing part type for grain lever.
Grain lever threshing device is a kind of full feeding tangential threshing device, the cylinder and the grid of the grain rod shape concave board in two parts, the roller of grain rod, drum shaft, wheel, etc, they are made between welding.
Screening device Screening device is mainly completed by grid type hollow board, it is made of a certain number of bar and two main beam and two vice beam, gap between every two bars can be corn gets stuck, and then rapidly spinning lines pole corn forcibly threshing roller will be stuck, of course, whether at work or when installation, grid type hollow board is fixed.

Relative density and average grain size were increasing with the increasing of sintering temperature, and fracture form is intercrystalline crack in 1500ºC and transcrystalline crack in 1700ºC. 97.3% relative density and 850nm average grain size were deserved at 1700ºC.
This was mainly due to the α-AlN grain grown significantly faster than the β-Al2O3 grain growth because of phase transformation [9].
It can be seen from these pictures that fracture form is intercrystalline crack in 1500 ºC with a large number of holes existing on fractured surface, which indicated that relative density of sintering materials is worse.
Fig. 2d, e and f show that average grain size were increasing with the increasing of sintering temperature.
It can be seen from the table that relative density and average grain size were increasing with the increasing of sintering temperature. 97.3% relative density and 850nm average grain size were deserved at 1700 ºC.

The Co grains in the films show hcp structure with (11 20) preferred orientation.
According to the Zener criteria[8], the larger the number of particles available in the matrix, the finer the grain size of matrix will be.
The pure Co film has larger Co grains than the composite coatings and three or four magnetic domains occurred in one grain, as shown in Fig. 9(a).
Firstly the Al2O3 reduces the grain size of Co during the electrodeposition process.
The Al2O3 nanoparticles reduce the Co grain size by increasing the heterogeneously nucleation sites and retarded the grain growth of the matrix.

All films exhibit highly twinned grains.
This leads to reliability problems reinforced by the copper elastic anisotropy and the increasing number of interconnect levels required by design laws.
Grains are delimitated by High Angle Grain Boundaries of weak atomic coherence (HAGB) in black.
Table 1 lists the parameters of these distributions for each film where N is the number of crystallites, d50% is the median size, σlog is the standard deviation of log-normal law and dmax is the maximum size.
Stress induced by grain growth Grain boundaries loss associated to the grain growth induces tensile strain for films constrained on a substrate.

The main changes in microstructure caused by Ca addition were the grain refinement in the as-cast alloys and the formation of new Al2Ca phase along the grain boundaries.
Grain size was also measured by the linear-intercept method.
The grain size decreased significantly from 200µm in AZ91 alloy(a) to about 110µm(c) with increasing Ca content.
Thus it can be concluded that with the addition of Ca, two microstructural changes can be observed: First, the grains of the matrix were finer than those of AZ91 alloy.
Second, a large number of Mg17Al12 disappeared and a new Al2Ca phase was formed as shown in Fig. 2(b).

The microstructure of the steel consists of equiaxed ferritic grains which average grain intercept length at the principal directions of the sheet are 23.9 µm (RD), 21.4 µm (TD) and 15.9 µm (ND).
Various types of particles were found homogeneously distributed embedded in the ferritic matrix in either grain boundaries or inside grains although it was more common the first ones.
The fraction of titanium particles is predominant in the material with around 83% of the total number of particles and their shape is close to cubical with an equivalent length of 2.54 µm.
A concentration of these dislocation features were observed close to the grain boundaries.
Acknowledgements This research was carried out under project number MC5.05220 in the framework of the Strategic Research programme of the Netherlands Institute for Metals Research in the Netherlands (www.nimr.nl).

Superplasticity usually requires a homogeneous fine grain size below 10µm with no significant growth during deformation [2].
The grains are equiaxied with average grain size of about 5µm for as-ECAEed material and about 10µm for as-rolled material, respectively, and the I-phase is fragment and distributed more randomly in the matrix as compared with that in the as-cast state.
However, grain sizes observed from gauge section almost did not change too much in both state materials.
A large number of thermal stable I-phase particles in the alloy can be contributed to effectively prohibit microstructural evolution of the α-Mg matrix, which makes the microstructures be more stable against coarsening during superplastic deformation [5].
While at 400°C, because of grain growth, the deformation in coarser grains may dominate by dislocation creep through dislocation glide/climb process [8].

Introduction It is acknowledged that severe plastic deformation (SPD) of bulk metallic materials leads to physical and mechanical properties significantly enhanced compared to those of coarse-grained materials due to extensive grain refinement [1-6].
Studies dedicated to the SME of the Fe based SMAs have emerged in large numbers, especially, the Fe-Mn-Si SMAs have been used for pipe couplings, fishplates and pre-straining rods that are based on constrained recovery Shape Memory Effect (SME) [22].
Annular dark-field (ADF) was used to improve grain visibility.
In the section denoted 1 (Fig. 4a and b) the austenitic grains were not distinguished and shearing bands may be observed.
The average grain size is about 190 nm, the smallest grain size highlighted is 0.083 nm and the largest is 487 nm.