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Cell blocks consist of a large number of dislocation cells (subgrains) and align in shear direction.
Fig. 2(a) shows the variation of the average subgrain and grain size against the number of passes determined by EBSD.
Fig. 2(b) shows the variation of the dislocation density against the number of passes.
The variation of (a) the average sugrain/grain size (b) the dislocation density (c) the fraction of HAGBs and (d) average misorientation angle for Cu, Ag, Cu-6.8Al, Cu-1Mn and Cu-5Ni processed by ECAP through different number of ECAP passes.
The fraction of the HAGBs is plotted in Fig. 2(c) as a function of the number of passes and comparable results for average misorientation angle is plotted in Fig. 2(d).

Relationship between Grain Growth and Formation of Fracture Surface of Ultrafine Grained Cu in High-Cycle Fatigue M.
In other words, oriented slip bands inside the areas increased their length and number with cyclic stressing.
Subsequent stressing brought a further increase in both grain size and number/length of slip bands.
oriantated grains.
Summary Marked grain coarsening occurred and slip bands were developed in the coarse grains.

It was observed that the ultimate tensile strength (UTS) increased with increased number of passes.
On the other hand, the number of research works as to SPD of commercial medium carbon steels is still limited [9,10], probably because systematic SPD processing is relatively difficult in steels with higher flow stresses.
The warm ECAP pressing at 400°C was performed and billets were subjected to higher to number of passes, N = 4, 5, 6 respectively.
In deformed ferrite grains the parallel bands are formed in elongated grains, Fig. 3a.
Increasing number of passes to N = 6, (εef = 4), in the deformed ferrite grains the submicron grains with high angle boundaries were more frequently observed, as documented in Fig. 3b.

Recent experiments showed that the XRD patterns of the nanostructured materials produced by SPD are characterized by a number of specific features in comparison with the patterns of corresponding coarse-grained materials [3-5].
A concurrent effect of a whole number of structural factors (small grain size, large nonuniform distortions of crystal lattice) on X-ray diffraction in SPD nanomaterials results in considerable difficulties in the interpretation of XRD patterns and, correspondingly, in the determination of the structure parameters of these nanomaterials by the XRD method.
When specifying the EGBDs density value in the nanostructured material we assumed that each crystallite contains a certain number of the dislocations (N) with Burgers vector b at its faces, so that these parameters correspond to the specified linear EGBDs density 
 at a given grain size d; i.e.
The grain size was about 170 nm.
However, the grain growth was not observed.

Introduction In order to improve the mechanical properties such as strength and toughness, a large number of studies have been made on the grain refinement [1-3].
Grain size in recrystallization field was smaller.
The average of the initial grain size was 0.05 mm.
Grain size increased with increasing the time interval.
The grains obtained by the collision of two times were refined and the field of the grain refinement expanded.

When the boundary plane is exactly on {110} in the grain B, it is about 8° from {010} in the grain A.
Transmission topograph of migrating asymmetrical grain boundary Σ5 where the initial boundary plane is close to {010} in the left grain A and to {110} in the right grain B.
Only one grain was visualized in our experimental setting.
When the grain boundary curves and migrates it changes the plane orientation via the {110} plane in one grain and simultaneously via the {010} plane in the other grain.
Qualitatively much larger number of observations can be collected in comparison to classical heating/cooling cycles.

The average grain size was about 10 mm.
Upon further processing to total strains of about 4 the number of the newly developed fine grains increases, resulting in UFG microstructures.
This is associated with rapidly increased number of low-angle dislocation subboundaries involved by plastic working.
It should be noted that some of these grains contain the annealing twins, which are indicative of grain boundary migration.
The local grain boundary migration taking place after large strains promotes the development of equiaxed DRX grains at 600-700°C.

As the data submitted in work fail contain enough observations, it is necessary that a results number allowed to make adjustment with the minimum error.
Summary Using the statistical analysis technique of size grains distribution histograms it is shown that when forming of a grains structure in single-phase metal materials processed by HPT, several groups of grains with different characteristics having various mobility of grains borders can be formed.
Semionkin, Mössbauer Spectroscopy of Grain Boundaries in Ultrafine-Grained Materials Produced by Severe Plastic Deformation, Bull.
Stolbovsky, Emission Mössbauer spectroscopy of grain boundaries in ultrafine-grained W and Mo produced by severe plastic deformation, Phys.
Stolbovsky, Emission Nuclear Gamma-Resonance Spectroscopy of Grain Boundaries in Coarse-Grained and Ultrafine-Grained Polycrystalline Mo, Defect and Diffusion Forum. 364 (2015) 147-156

An RVE must include a large number of the material’s micro-heterogeneities (e.g., grains, inclusions, voids).
Specific mechanisms of grain refinement are studied in a number of publications (see, for example, [14, 23]).
The above view explains a number of effects observed during simple shear, including the following: 1.
This can be done using either the yield stress YS or the Vickers hardness number (HV) of the specimen.
Fig. 7 shows the shape of the inclusion after a given number of shifts.

The adsorption process is determined by the concentration of the solute in the fluid next to the solid grain in individual pores.
The adsorption is represented as an equilibrium process where the chemical potential of the solute in the fluid next to the solid grain is equal to the chemical potential of the solute adsorbed to the grain [12].
Therefore, the coarse-grained Peclet number (Pe) can be obtained by the case of a non-adsorbing solute (i.e., k=0) in Fig.2.
As the upscaled Peclet number has been estimated, only two upscaled parameters, ka* and kb*, are left to be determined as a function of pore-scale parameters.
The larger scale kinetic adsorption parameters are obtained as a function of pore scale parameters such as Peclet number and distribution coefficient.