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Aibin Ma et al. reported that the grain or grain fragment size of the Al- 11mass% Si has been refined after only 4 passes.
In spite of a further increase in the number of RD-ECAP passes to 32, the alloy maintained the same grain or grain fragment size of about 200-400nm [9].
Plenty of conherent dimples disperse the fracture surfaces of UFG sample due to the smaller grain size and high volume fraction of grain boundaries.
Since the degree of boundary modification and the fine particles content usually increase with pass number of ECAP, it can be assumed that various materials after grain refinement via ECAP processing might overcome their ductile-to-brittle transition and achieve high low-temperature impact toughness, which unique phenomena should not exist alone in nanostructured Ti and UFG SiCp/ZL108 MMCs.
The incremental value of impact toughness of UFG materials after SPD processing may be related to grains or grain fragment boundary modification.

When silicocalcium was introduced as a deoxidizer at the amount of 1.5 kg/ton (sample # 4), the number of oxisulphides decreased while the number of sulphides in the steel grew by 2.5 times.
In case if aluminum and silicocalcium are introduced simultaneously and at the same quantity of 0.7 kg/ton (sample # 5), a noticeable decrease in the number of sulphides is observed (their amount is the smallest compared with other deoxidation methods) and a small number of oxides precipitate.
Fine globular oxisulphides inside the grain, 500 ×.
A decrease in the amount of oxides and an increase in the number of oxisulphides with a heavier concentration of such a reactive deoxidizing agent as aluminum is accompanied with an equable decrease in the number of sulphide inclusions (samples 1-3).
The dependence of sample contamination with sulphide inclusions inside grains and along grain boundaries on deoxidation method is presented in Fig. 5 It can be seen in the plot that an increase of such deoxidizing agent as aluminum (0.7 and 1.5 kg) results in a higher sulphide concentration inside the grain and, consequently, decreases the amount of sulphides at grain boundaries.

Simulation model Cellular automata are mathematicl descriptions of physical systems for which space is divided into a great number of individual cells, time is alse discretized.
Table 1 Parameters of the simulation model Cells Number N Orientation S Simulation Step /CAS Particle’s Shape 500×500 1000 2000 circle Results Before considering the evolution of the simulated material, it is useful to examine the behaviour of a single circular grain in the presence of the second phase particles[3].
The slope (n) of their fitting line decreases gradually, this means that n is not a constant number and it decreases with the increase of simulation time when the matrix contains second phase particles.
As the simulation time crease, grain boundaries are pinned, and then the grain growth is inhibited.
In Model B (or Model C), the grain growth has been under way for some time, the grain size has become big.

The grain size of Specimen #4 shows much finer grains with the minimum size reaching about 1 micron.
During the transformation, the carbon atoms diffuse to the grain boundaries with the growing ferrite grains to form carbon-rich retained austenite foil in the grain boundaries.
This might indicate why the grain boundaries are rough.
Wung, Grain Fining Theory and Control Technology of Ultrafine Grain Steels, Metallurgical Industry Publisher, Beijing, 2003 [3] W.Y.
Choo, New Challenge to Develop Ultra Fine Grain Steel with 1micron Grain Size, J.Kor.

Usually, grain growth means coarsening, i.e. the growth of mean grain size.
The number of scallops decreases with time as .
We treat the anti-phase domains as grains and boundaries between the anti-phase domains as grain boundaries between grains with different orientations.
The “time” at the abscissa in Fig. 2 is actually (36) The ordinate in Fig. 2 is a mean number of atoms per a cross-section of a domain satisfying the condition of the ordered phase.
The exchange is not accepted if the randomly generated number from interval (0.1) is larger than.

After HPT, the grain size was found to have a mean value about 100 nm for both alloys.
The applied pressure of 6 GPa and number of rotations 20 were used to process the 1570 alloy.
A mean grain size was estimated from TEM dark field measurements in torsion plane over 350 grains from an area situated at the middle of an HPT disc radius.
It is interesting to note that these segregations seem to spread over distances much larger than conventional grain boundary segregations observed along equilibrium grain boundaries.
In addition, dislocations are generated at grain boundaries and move through a grain to be captured by an opposite grain boundary.

It is clear form Equ.3 that the impedance of a sample not only depends on its material properties, but also depends on many other items, such as the number of interfaces in the sample, the thickness of different layer, and the exact material properties of every layer in the sample.
For example, controlling the volume rate of doping conductor grain and magnetic grains can adjust the effective electro-magnetic parameters of the composite material.
In this paper the attention is focus on the effect of adding conductor grain into magnetic material, the reason for this is conductor grain can change the permittivity of composite in wide range even the grain volume is very small.
is the grain volume rate, and is a geometric constant which is 1/3 for ball grains..
In calculation the sample thickness is set 0.5 cm and the conductor of grain is 100S/cm.

Barn Grain Temperature Information Error Controlling Method Based on Limited Feedback Compressed Sensing As more feedback data will increase the bandwidth, there exists a question that what date should be feedback in compressed sensing online monitoring of grain information.
Suppose thatis the grain temperature andis the sampled vector by compressed sensing, the sampled vectoris sent to the receiver; 2.
is a the index set of original temperature according to,is a the index set of original temperature according to; Comparing two sets of elements, an error is detected if there are different elements, and the number of errors can be calculated by the formula (3), which Card is the number of the set
Grain temperature changing law research.
Grain Storage Technology Communication, vol. 5, pp. 51-52, 2005.

The main parameters that characterize the geometry of the WSW, are the number of diamond grains per unit area of the tool surface, law of the grain vertex distribution in height and radius of the rounding grains vertexes.
Number of grains are lower evenly than the actual on (20-25)% in the considered depth.
The number of contacting grains will be different for instruments with different elastic ligament characteristics, and power settings in the contact zone will change respectively.
i - number of the interval where these grains are located (it should be calculated from the interval where the most projected grains are located in).
When grinding with a thin elastic diamond tool the number of active grains is determined by the ligament compliance: the more ligament compliance increases, the more number of active grains become.

The fraction of the spot overlap depends on the number of grains, the sample-to-detector distance, the detector resolution, the crystal structure of the sample and the mosaic spread of the grains.
The overlap fraction for the TTF-CA samples was studied as function of the grain number, the sample-to-detector distance, and the data resolution.
Fig.1 shows the overlap fraction as a function of the sample-to-detector distance for 100 grains(a), and the data resolution and the grain number at the sample-to-detector distance of 50mm(b).
It is evident that the overlap fraction increases with the increasing number of the grains.
Crystallographic accuracy of structure solution for individual grains from the TTF-CA polycrystalline sample Grain R(int) R(sigma) GooF R1 1 0.0269 0.0268 1.130 0.0234 2 0.0229 0.0212 1.101 0.0203 3 0.0232 0.0230 1.090 0.0193 4 0.0253 0.0261 1.025 0.0195 Conclusion The overlap fraction for the TTF-CA samples was studied as function of the grain number, the sample-to-detector distance and the data resolution.