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A number of nonequilibrium nanocrystalline fcc solid solutions Cu1-x-Agx (x = 0,1; 0,2; ... 0,9; 1,0) were obtained by mechanical alloying of powders by the use of high pressure torsion.
The obtained alloys were found to be characterized by a positive excess over Vegard law, ~ 20 nm grain sizes, a microhardeness of 4.5-6 times higher than the Cu and Ag one and brittle type of the fracture surface.
High pressure torsion (HPT) is a mechanical alloying (MA) technique, the purpose of which is to obtain bulk ultrafine-grained alloys by imposing an extremely high plastic strain [5,6].
A preventing stationary anvil force F vs. moving anvil rotation angle φ = 2πn (where n - number of revolutions) was measured in situ under pressure.
A characteristic feature of the structure as a kind of buckwheat-like fracture, is a complete coincidence of grain sizes in the structure and on the fracture.

The primary crystallite size of YAG phase is calculated to be ~46 nm and the crystal grains grow with preffered orientation (444) in the internal network.
The average secondary particle size is estimated to be ~8mm and the larger grain size is due to the particle aggregation.
Compared with the diffraction spectrum of the powder sample, the peak number of the bulk sample decreased obviously.
The strongest peak corresponding to crystal face also change from (420) to (444), and the dominant peak reveals that the crystalline grains grow with highly preferred orientation (444) in the bulk YAG glass ceramics.

Wood is distinguished from other civil engineering materials by its manifest orthotropism which increases considerably the number of mechanical characteristics to take into accounct.
As a result, mechanical properties are collectively described only for directions parallel to grain and perpendicular to grain
● Compression Wood can be subjected to compression parallel to grain, perpendicular to grain, or at an angle to grain, or at an angle to grain（Fig.1）.When compression is applied parallel to grain, it produces stress that deforms the wood cells along their longitudinal axis.
Compression applied at an angle to grain produces stress acting both parallel and perpendicular to the grain.
● Bending Bending produces horizontal shear parallel to grain, and compression perpendicular to grain at the supports.

Actually in the last years several research groups all over the world have been working on such topic with a quite large number of publications which can be found in literature focusing on different aspects of the process such as microstructural issues, process parameters influence, joints fatigue life and material flow analysis.
In this way the conditions for the activations of the grain growth phenomenon were not reached.
Looking at Figure 4, a similar phase distribution is found, i.e. three different areas can be identified within the SZ, characterized by mixed alpha and alpha+beta acicular grains, DRXed alpha grains and very fine DRXed alpha grains.
At the sides of this area, a smaller zone is found with mixed alpha and alpha+beta grains.
Finally, close to the bottom of the pin the fine alpha grains are observed.

In the meantime, the outer layer was finer-grained, but more so for the coating on the Ni-CeO2 codeposited sample.
The pits formed as a result of the faster etching at the grain boundaries (especially at the junctions of triple grain boundaries) than the other place.
At the approaching content, the number per unit volume of particles of CeO2 is theoretically larger than that of Y2O3 in the deposits by eight orders of magnitude.
Afterwards, they would segregate to the scale grain boundary.
In this work, the formation of finer-grained chromia on the RexOy-modified coatings than on the RexOy-free coatings may be an evidence of segregation of Re ions along the oxide grain boundary, because the segregated ions exerted a "solute-drag" effect to block the oxide grain growth [22].

The grain size specified by the manufacturer is 60-80 % of particles with a diameter over 100 μm.
The grain size specified by the manufacturer is 50 % of particles with a diameter of 3.5-5.0 μm.
The specific surface area, which indicates the grain size and character of the particles.
The current depends on the water content, preferably the current is conducted by means of contact between graphite grains, where at a lower water content (30-50 %) the low contact of larger grains of coarse Graphite type (A) is significant.
In the last zone, at a humidity of about 30 %, the current leads very little through the ions of the contained water and jumps directly between the graphite grains, the farther apart the graphite grains are, the lower the conductivity.

Later on Delannay et al. [5], Van Houtte et al. 6] and Crumbach et al. [7] have developed n-point models in which the plastic power dissipation is optimized over a set of n individual grains which comply with the imposed macroscopic displacement as an aggregate set, but of which the n individual grains are each allowed to violate the Taylor condition whilst observing internal boundary conditions that are associated with the specific geometry of the n grains stacked together in the aggregate.
The LAMEL model is a 2-grain interaction model which can accommodate arbitrary but opposed levels of ε13 and ε23 shear strains.
ALAMEL model is a more sophisticated version of the LAMEL model which also takes into account strain gradients from the grain boundary towards the grain interior.
This is an 8-grain interaction model which also allows for accommodation of ε13 and ε23 shears at the 12 internal grain boundaries occurring in the 8 grain aggregate.
This may indicate that the nucleation of the diffusion controlled phase transformation is an essential prerequisite to generate a sufficient number of new orientations at the surface which afterwards may be selected for growth according to the above mentioned energy criterion.

Coarse precipitates of primary γ＇can be clearly seen at the grain boundaries which grow coherently into ellipsoidal or disc-shaped particles.
The average grain size of γ matrix is about 35μm and the volume fraction of primary γ＇is about 17% measured by Image-pro Plus software.
The end of work softening is considered to be completion of first wave of recrystallization which proceeds by nucleation of necklaces of new grains until the initial grains are consumed.
The dynamically recrystallized grains appear at the grain boundaries of elongated grains which are examined in the heavily deformed shear band regions.
The difference size of maximum grain and average grain is about 100μm.

The lattice constant (a) and grain sizes (D) is calculated with the Eq.: (1) and Eq.: , (2) respectively.
A large number of defects is formed in the films during sputtering process and exists in the form of grain boundary volume and point defects, and then acts as pinning sites for domain walls [6], which can result in large Hc.
The second reason may be due to the small grain size in the films induced an increase in the number of grain boundaries.
At low level fluence, as the accumulation of defects in the Mn0.5Zn0.5Fe2O4 thin films induced by SHI irradiation, Hc increases while Ms decreases, which is mainly because the crystal structure of the Mn0.5Zn0.5Fe2O4 thin films has been broken by SHI irradiation and a number of grain boundaries increase significantly.

Crystallographic data were expressed by phase map with grain boundaries.
SEM image and phase map clearly show that the darkly etched region contains a large number of second phases with a bcc structure.
In the darkly etched region, a large number of austenite grain boundaries are deeply corroded.
To clarify a reason for the deep corrosion of the austenite grain boundaries, TEM observation was conducted.
This would be a reason for deep corrosion of the austenite grain boundaries in this region.