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For grain size estimation Met-Ilo software was used [21].
Due to its specific morphology, grain boundaries in microstructure of massive phase gm are poorly or hardly visible, which practically makes it impossible to determine grain size in this phase.
At the same time, it should be short enough not to result in unintentional grain growth.
Effect of cycle number on the microstructure of Ti-47Al-2W-0.5Si alloy Fig. 9.
Effect of cycles number on the hardness of Ti-47Al-2W-0.5Si alloy The Ti-47Al-2W-0.5Si alloy after cyclic heat treatment conducted under optimum conditions for it was put to under-annealing (Stage 3) at the temperature of two-phase a+g area to obtain the expected grain refinement due to decomposition of defected massive phase gm caused by gm®a+g transformation.

Grain Boundary Segregation and Grain Boundary Diffusion of Carbon in Niobium.
Introduction Grain boundary (GB) segregation of a number of microalloying elements like C, P, S, B and others strongly affects the mechanical properties of the structural materials [1].
This fine-grained structure was very unstable and the grains grew intensively during heat treatment.
The optimal grain structure with grains of about 200 µm was obtained by annealing the specimens at 1373 K for 10 hours.
Gust: Fundamentals of Grain and Interface Boundary Diffusion.

However a very large number of measurements are necessary, because the spot diameter is very small.
It is well known that super-abrasive grain represented by a diamond abrasive grain is formed a wear-flat area at the most highest part of grains [6].
Comparison of images by different irradiation lights 2.2 Measurement of cutting edges It is well known that super-abrasive grain represented by a diamond abrasive grain formed a wear flat at the most highest part of grains.
Extracted abrasive grains Fig. 9.
Analysis results Number of grains 4 Proportion of grains 5.44% A Area of grain 5781 [pixel] C Area of grain 4483 [pixel] Internal lack 293 [pixel] Internal lack 43 [pixel] External lack 36 [pixel] External lack 12 [pixel] B Area of grain 1969 [pixel] D Area of grain 5381 [pixel] Internal lack 138 [pixel] Internal lack 267 [pixel] External lack 378 [pixel] External lack 11 [pixel] Fig. 10.

The number of passes at each temperature was N = 3.
The term "ultrafine grain structure" is referring to nanostructure with grain size of less than 100 nm, and submicrocrystalline structure with grains between 100 and 1000 nm.
Currently, there are two main approaches for refining ferrite grains down to the ultrafine grain range in bulk steels.
The effect of strain non-uniformity across the plane X upon three-fold die pressing affected structure forming regardless the number of ECAP passes involved.
As pointed out previously, a multi-pass ECAP produces remarkably uniform microstructure if the number of passes is higher then three and if the angle of intersection of channels is φ = 90°.

Effect of alloying elements and impurity (N) on bulk and grain boundary cohesion in Cr-base alloys V.N.
Introduction Chromium has a high melting point (~ 1875°С) that refers it to a number of refractory metals [1, 2].
We chose a special high angle grain boundary Σ5 (210) [100] and a free surface (210) for investigation.
The values of the partial cohesive energy χi for a number of alloying additions to chromium.
The values of the parameter η for a number of alloying elements and impurity N in Cr-base alloys.

That is, one grain consisting of bi-crystal (grain A) had the crystal orientation whose Schmid factor for prismatic slip is 0.5.
The crystal orientation of the other grain (grain B) was slightly deviated from that of grain A.
Although a number of crystal plasticity models have been proposed and described the anisotropic deformation behaviour of polycrystalline magnesium [1, 2], single crystal parameters used in the calculations significantly differ to the experimental values of CRSSs [3, 4].
The Schmid factor of a Prismatic slip system in grain A is 0.5 and the crystal orientation of grain B is slightly deviated from grain A.
Analyses of tensile loading of single crystal models with Euler angles for grain A and grain B are also performed.

From the zinc diffusion profiles were deduced the volume diffusion coefficient and the product δDgb for the grain-boundary diffusion, where δ is the grain-boundary width and Dgb is the grain-boundary diffusion coefficient.
However, in spite of a number of previous works on zinc diffusion, oxygen diffusion, and defects in ZnO, there is still lack of conclusive data about defects and diffusion in this material.
Determination of the grain-boundary diffusion coefficient.
The authors of the present work have performed a limited number of measurements of zinc diffusion coefficients in Al-doped ZnO in order to obtain information about the zinc diffusion mechanism in ZnO.
Fundamentals of Grain and Interphase Boundary Diffusion.

By increasing the embryo density in austenite through deformation, the number of martensite grains increases.
Therefore, it is not obvious that the grain size of BM grains can be represented by the width of grains.
BM grains have peculiar anisotropic geometry: two coarse grains collide to form one BM grain.
(a) Definition of the grain width of LM grains and BM grains.
When a microstructure consists of only LM grains, the index of the grain size distribution is the width of LM grains.

Then the size of austenite reduces because the number of austenite crystal nucleation is larger [5].
After measuring the grain size, the averaged value was the grain size.
The grain size curves under four different strain rates Dimension of the grains/mm . 4.
Because there is non-homogeneous nucleation in grain boundaries, new grains generate in the grain boundary continuously.
So these fine equiaxed grains occur only in the grain boundaries.

SB SD SB A B Journal Title and Volume Number (to be inserted by the publisher) 3 Figure 3: Evolution of the (sub)grain size (a) and the fraction of low angle boundaries (LAGBs) (b) with annealing time at 500°C and 600°C.
Grain Growth.
When the CRX is complete, i.e. when the dislocation density in the (sub)grain interior has reached an equilibrium value and the former dislocation boundaries have become equilibrium grain boundaries, the grain assembly continues to grow, now solely driven by the decrease in total grain boundary energy.
Journal Title and Volume Number (to be inserted by the publisher) 5 relatively small grain size of about 2µm after 100h at 600°C.
Development of Bimodal Grain Size Distribution.