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The Issue of Increasing the Products Durability Made of Fine-Grain Concrete E.O.
Constant long-term condition monitoring of a number of road surfaces experimental sections allowed to carry out products defects systematization and to classify the reasons of their emergence.
The influence of grain composition of fillers on properties of hard-pressed concrete was estimated at the first stage.
It should also be stopped on the results of the hard-pressed fine-grained concrete corrosion tests with the aim of evaluating the corrosion resistance of fine-grained concrete in conditions of the second and third types corrosion (according to classification of V.
Lotoshnikova, Hard-pressed fine-grained concretes with damping additives, materials of the theses, Rostov-on-Don, 2005

Furthermore, the grain orientation effects of BNTV-y ceramics on their piezoelectric properties are discussed using the grain-oriented ceramics prepared by the hot forging (HF) method.
Grain-oriented samples were prepared by the hot-forging method (HF).
RESULTS AND DISCUSSION X-ray diffraction patterns for (OF) BIT-Nd, BIT-V and BNTV ceramics show single phase of bismuth layer structured compounds with the layer number, m=3.
It is considered that these small grains prevent large grains from being orienting.
On the other hand, the number of small grains of the (HF) BNTV-y0.25 ceramic� shown in (a) are fewer than those of the (HF) BNTV-y0.75 ceramic.

Research indicates that grain size and concentration of abrasive material should be reasonably selected based on the surface roughness.
And Inhomogeneity of concentration distribution along wheel circumference will result in heterogeneity of insulator layer state, which will bring difference in the number of abrasive grain in the grinding area, thereby changing the actual cutting depth of every abrasive grain.
Selection of grain size and abrasive material concentration It is known well enough that grain size and concentration of abrasive material should be choiced rightly based on the surface roughness and maching efficiency.
Inhomogeneity distribution of various components on the surface of abrasive tool will result in heterogeneity of insulator layer state, which will bring difference in the number of abrasive grain in the grinding area, thereby changing the actual cutting depth of every abrasive grain.
Main conclusions of this paper are as follow: 1) Abrasive grain size and diamond wheel concentration should be reasonably selected based on the demand of surface roughness, and each grinding depth and feed frequency in vertical direction of maching surface should always be scientifically determined. 2) Inhomogeneity of concentration distribution along wheel circumference will result in difference in the number of abrasive grain, thereby change the actual cutting depth of every abrasive grain.

Further analysis indicates that this difference is due to the number of grains in the direction of thickness of the material: more grains give more grain boundaries, which allows more strain of the grains.
Compared to this, the grains in forming zones are different.
Fewer grains mean fewer grain boundaries.
This procedure causes, that all grains within the forming area are strained, like the elongation of grains for Al99.5 with thickness of 100 µm.
Conclusion From the reported work it can be concluded: · The LDR in micro deep drawing is smaller than in macro deep drawing; · The forming limit of thin foils is lower that thicker foils; · The number of grains involved in the micro forming process affects the forming limit essentially.

A coarse-grained parallel model has been used to implement the PLCA.
According to the nature of the population structure and the mechanisms of reproduction, the parallel model for PEAs can be classified into three main types: master-slave model, fine-grained model and coarse-grained model [11].
In the coarse-grained model the whole population is divided into several subpopulations (Fig.1c).
Obviously, the communication overhead increased linearly as the number of processors increased.
A coarse-grained parallel model is used to implement the PLCA.

As shown in Fig. 3(a), the grains of GH4037 samples heated at 1310℃ for 30min differed from one another in size and shape, and there existed a large number of lamellar twins.
In Fig. 3(b), the grains became larger and more round than that at 1310℃, and the number of lamellar twins decreased.
Besides, a large number of lamella-like straight annealing twins appeared in the microstructure of semi-solid billets with such high solid fraction.
With the increasing of soaking time, the number of intragranular liquid droplets decreased and the solid grains became larger and more globular.
Therefore, the large solid grains were divided into some tiny grains.

(a) strong axial orientation columnar grain, and (b) equiaxed grain Rolling experiment.
When the cold deformation further increased to 61.86%, a number of fine bending deformation bands formed with the axial of the tube to be 15- 45° in the columnar grain, as shown in Fig. 2e.
Grain boundary strengthening effect depends on the grain boundary misorientation.
When the cold deformation further increased to 61.86%, a number of deformation bands were clearly observed, as shown in Fig.3e and 3f.
Axial Radial Axial Axial Radial Radial There were a large number of grain boundaries in the pure copper with equiaxed grain than columnar grain, leading to a more obviously prevent effect on dislocations during plastic deformation.

The size of the grains is controlled by a packing limit in order to obtain realistic mass transfer values during the grain-to-grain interaction in the control volume.
The number of grid cells has been increased from 180 to 4300 in half of the symmetrical domain.
The grains sink down and settle at the bottom region.
The number of grid cells has been increased from 180 to 4300 to define an optimal grid size, to prove the reliability of model implementation.
The results show that the macrosegregation pattern does not change significantly above a well-chosen number of grid cells, at least from 2780 cells in our case.

The value of two characteristic diameters was recorded for each examined grain with the ratio of these characterizing the shape of the grain (some measurement results are shown in Table 3).
Both the mean grain size (~50-60 μm) and the scatter of grain size is greater in the case of the austenitic microstructure of the Grade X80Mo0 specimen than in the case of the Grade X80Mo2 specimen having a higher Mo content.
In the case of this latter specimen the mean grain size of the microstructure is only 25-35 μm and the grain size distribution is much more homogeneous.
Figure 11: The image of Grade X80Mo0 specimen taken with optic microscope (original magnification: 500x, reagent K) Figure 12: The image of Grade X80Mo2 specimen taken with optic microscope (original magnification: 500x, reagent K) Table 3: Austenite grain sizes Serial number of austenite grains investigated 1 2 3 4 5 6 7 8 9 10 11 12 X80Mo0 Austenite grain diameters (μm) 41.3 17.2 56.9 13.8 24.1 81 65 166 108 59 109 65.8 23.3 11.9 52.1 13.8 19.5 43.5 41.1 49 77 42 68 65.1 X80Mo2 Austenite grain diameters (μm) 12 41.4 29.2 26.3 34 11.8 31.6 13 33.7 10 28.5 12.2 11.3 40.4 26.6 16.1 23.7 8.8 27.7 10.6 30.4 6 26 9.7 Summary In the course of our experiments we have developed an etching procedure by means of which the austenite grains formed after roughing can be made visible in the case of Grade X80Mo0 and X80Mo2 microalloyed steels.
Vander Voort: Revealing Prior-Austenite Grain Boundaries in Heat-Treated Steels, 2010.

Only a small number of grains are <100>//ND and <110>//ND orientation texture.
And it has an in-homogenous grain size distribution with an average grain size of 10μm or so when the sample annealing 180sec.
The deformed stored energy of {111}<110> orientation grains is higher than {111}<112> grains.
The deformed bands and grain boundaries are benefit for the nucleation of {111}<110> and {110}<001> orientation grains.
The low angle grain boundaries are higher for the sample annealing 60sec and the high angle grain boundaries are higher for the sample annealing 90sec.