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The TiN grain size was found to increase with increasing TiN content, resulting in a decreasing hardness and strength.
The commercial powders are yttria-free monoclinic ZrO2 (Tosoh grade TZ-0, Tokyo, Japan; 27 nm grain size), 3 mol % yttria co-precipitated ZrO2 (Tosoh grade TZ-3Y, Tokyo, Japan; 27 nm grain size) and jet-milled TiN (Kennametal, Victoria, USA; 1.03 µm grain size).
The composite with 35 vol % TiN has the smallest TiN grain size, which is found to increase with increasing TiN content (Fig. 1).
The Vickers hardness and bending strength of the composites decreases with decreasing ZrO2 content, what can be attributed to an increasing TiN grain size with increasing TiN content.
STRP 505541-1 and the Flemish Institute for the Promotion of Scientific and Technological Research in Industry (IWT) under contract number GBOU-IWT-010071.

Although the broad pattern of reactions and microstructural development are known, a number of important questions remain unanswered.
Electron microscopy techniques have now been used in a very large number of studies on cement and concrete.
Through the use of STEM imaging of early age hydrated cement pastes, Scrivener [14] reported an important microstructural aspect of the early hydration of Portland cement is the formation of a shell of hydration products around cement grains.
Using wet-cell TEM and SEM-BSE imaging, Scrivener [18,19] observed the formation of an ill crystallised product on the surface of C3A grains hydrated in the presence gypsumafter a few minutes; and nucleation of short AFt rods out in solution.
[14] E.Gallucci, P.Mathur, K.Scrivener, Microstructural development of early age hydration shells around cement grains, Cem Concr Res, 40(2010): 4-13

In this panorama, as the effective interfacial contact area between the fiber and the grains increases, the number and depth of the grooves formed from the penetration of hard particles into the fiber increase, having, as a result, an extended plowing of the grains into the fiber body during the shear process, which gives a significant rise to interfacial strength and friction [10].
This occurrence is probably due to the relative size existing between the fibers and grains of the soil since a material composed of finer grains results in a much larger number of grain-fiber contact points [10].
In this sense, concerning the effectiveness of the reinforcement depending on the number of contact points, the effective contact area between grains and fibers directly influences the magnitude of friction and interfacial adhesion [42].
The occurrences present in Soil 2 can be justified by the fact that this soil has an opener granulometry and, consequently, a tendency to generate a smaller number of grain-fiber contact points.
On the contrary, with a finer granulometry, Soil 1 tends to have an easier fitting and penetration into the protrusions and indentations of rough fibers, which generates a greater number of grain-fiber contact points and, consequently, a greater interaction soil-fiber, in addition to an increased interlocking force and a friction coefficient, restricting the rearrangement of fibers at the shear interface.

The diffusion is known to be much more efficient at grain boundaries than inside the grains.
Moreover, grain boundaries have also a role of vacancy reservoir.
They are thus less sensitive to the grain boundaries effects.
The numbers give the energy differences in eV.
There is a small favorable energy balance due to the induced smaller number of broken bonds (0.4 eV and one M-P bond difference).

Metal cold brittleness is known to be primarily defined by grain size as well as other factors.
During ECAP, the route (Вс and С), cycle number, and pressing temperature varied.
To improve effectiveness of grain refinement and to get higher material strength, ECAP was preceded by quenching.
ECAP leads to structure formation with fragments of mainly grain type.
Tempering at 873 K, in its turn, results in certain grain growth to one to three µm.

The higher brilliant HEMS beamline is optimal for small grain size distributions and for single grain techniques, such as 3DXRD [11].
According to the low scattering angle of hard X-rays one can get complete Debye Scherrer rings for a number of reflections using area detectors of about 300x300 mm size.
Neutron diffraction is favoured for larger gauge volume and and coarse grained materials.
Due to the beam quality, beamlines for medium grain size and very small grain sizes complement each other.
Acknowledgement: The work has been funded by the German Ministry of Education and Research (BMBF) under the contract number 05KN7MCA.

To develop this microstructure, a number of methods have been presented, among which the controlled nucleation method reported recently has received a lot of attention [2].
The melt, containing a large number of these nuclei crystals, solidifies in the die, resulting in a fine globular microstructure.
Consequently, many grains having random orientations, are nucleated at the thin wall zone [7].
This may be attributed to the fine, globular structure and uniform distribution of primary α-Al phase and Si grain achieved in cooling slope casting.
These increases in hardness can be attributed to the fragmentation of Si grains, increasing dislocation density and grain refinement which were due to high strain induced during ECAP processing.

Savyolova 1, a 1 Moscow Engineering Physical Institute, 31, Kashirskoe shosse, Moscow 115409, Russia a borovkovm@mail.ru Keywords: Normal Distribution, Rotation Group, Statistical Simulation, Pole Figures, Orientation Distribution of Grains Function, Monte Carlo Method.
Monte Carlo method allows to calculate the orientation of grains function (ODF) and correspondent pole figures (PFs) using approximation by normal distributions [2].
It is also possible to estimate errors of ODF approximating by repeated simulation and calculation RP-factor between recalculated PFs by appropriate selection of sample volume parameter, which corresponds to the number of crystallites in the sample (Eq.2).
The following parameters were used: realizations number (e.g. the sampling array size) 10 000, and convolution factor 20.

However, the Mn-Cr-Ti-S sulfide domain may have an undesirable influence on end-grain pitting in ferric chloride test.
The number of pits away from the edges was counted, and a summary is shown in Fig. 4.
The number of pits seems to be giving more feasible results, if compared to prior tests.
Figure 4 – Number of pits in ground samples (left), and a depth distribution (right).
However, the Mn-Cr-Ti-S sulfide mode may have an undesirable influence on end-grain pitting corrosion.

The thicknesses of both Mg layer and ZK60 layer decreased gradually with the increasing of the ARB cycle numbers.
Mg layer was quite homogeneous after first cycle of ARB, however the ZK60 layer exhibits a bimodal grain size distribution with initial non-subdivided coarse grains and fine recrystallized grains.
After 3 ARB cycles, the microstructure of the multilayered composite consisted of alternate layers of fine ZK60 layers with average grain size of 2.3 µm and pure Mg layers with large grain size of about 24 µm.
The much finer grain size of ZK60 layer than that of Mg layer may be mainly attributed to the small precipitates in the ZK60 layer, which hinder the movement of grain boundaries and dislocations, thus, facilitate the stabilization of a finer grain size.
With increasing ARB cycles, the grain size of the pure Mg layer was refined gradually, which led to the decrement of damping capacity due to the strong pinning of grain boundary on dislocations[11].