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A laser is often considered to scribe the grain-oriented silicon steel surfaces after cold-rolling and annealing to reduce the core loss.
Introduction Grain-oriented silicon steels have a large market in the field of soft magnetic materials.
Learning rate, maximum number of epochs and MES goal were set to 0.1, 1000 and 0.1 respectively.
The training is terminated when the set MSE goal is achieved or when the maximum number of epochs defined is reached.
When the variation in the fitness values was smaller than 0.1 or the set maximum number of populations was reached, the process finished, and the optimal solution was output and saved.

Among these mechanisms one should list the followings. (1) The dislocation hardening associated with dislocation storage in the grain interior. (2) Hall-Petch or grain boundary (GB) hardening which is associated with grain fragmentation and with the barrier effect of GBs for dislocation movement
We say that "the number of small" when the structure is not yet converted into the granular type with prevailing high-angle grain boundaries.
There has been a plenty of evidence in the literature that the high-angle grain boundaries tend to form in f.c.c. metals at considerably higher strains (number of ECA-passes) than we imposed in the present work [2].
Surely, the number of passes which is required to form the high-angle grain boundaries is different for different materials, being dependent on various metallurgical factors such as the stacking fault energy, for instance.
Zehetbauer: in Ultrafine Grained Materials II / Y.T.

The massive ferrite separate out a small number of tiny carbides.
Fig.c) show that there are also a large number of sub-boundaries in the grain of massive ferrites and some small carbides that are precipitated along the grain boundaries.
The number of granular carbides significantly increases, and the particle size is larger.
A large number of carbides precipitations precipitated in the grain boundary between massive ferrite and bainite phase, which grew up from grain boundary to bainitic grains, and became the larger carbide particles at the junction of three grain boundaries.
The microstructure of 10CrMo910 steel after running 147,000 hours is still a large number of bainite and a small amount of massive ferrite; subgrain boundaries and dislocations significantly are reduced in transgranular of bainite; subgrain boundaries and dislocations almost disappear in transgranular of massive ferritic grain. 2.

During extrusion, more MgZn2 compounds were precipitated from the supersaturated Al matrix and observed on the grain boundaries and in the grain interiors.
The precipitates in the grain interiors are well distributed.
A number of fine particles are observed in the matrix.
Table 1 7×××serious aluminum alloy room-temperature properties with powder hot extrusion technique and traditional method Number Alloy Fabrication method σb/MPa σ0.2/MPa δ/% Ref.
The microstructure of powder is composed of Al matrix and MgZn2 phase on the grain boundaries and in the grain interiors.

The average grain size was about 10nm and the grain characteristic presented equiaxed morphology.
As everyone knows that nanocrystalline material possesses a large number of grain boundaries, dislocations and atomic level microstructural defects which can act as high diffusion paths to carbon atoms.
This result can be attributed to the grain refinement and micro-strain development.
The Fig.5(b) revealed that carbides scale in the outermost surface was about 20~30nm by randomly measured a large number of nanocrystalline.
(2) The grain size in the nanocrystalline layer was refined to nanoscale level with about 10nm in size and presented equiaxed grain morphology with random crystallographic orientation

When strain rate becomes to 100mm/s, the number of increasing dislocations are more than that of disappeared dislocations, so the saturated value of hardness of pure Cu comes to 178HV5 after only 3 passes.
With the increasing of passes, shear bands disappears and elongated sub-grains appears, then they turn to elongated grains as shown in Fig.2a and 2b. when processing passes exceeds eight, grains turn to equiaxial grains as shown in Fig.2c and 2d.
From the present literatures, high angle grain boundaries can be formed from dynamic recovery but it is one of conditions of ultra-fine grains with high angle grain boundaries but not the mechanism.
It is well known that grain boundary sliding can’t be produced from low angle grain boundaries.
Therefore, the grain boundary sliding mechanism can’t be started before the forming of high angle grain boundaries.

The degree of formation of nanodomains depends on the grain composition.
Thus, a number of studies have been carried out on microstructures in piezoelectric materials.
This implies that localized stresses may have accumulated in the grains due to densification by sintering.
Fig. 6 DF-TEM images of domain structures in a grain of PZT ceramics fired at 1100 °C for (a) 1 min and (b) 2 h.
The degree of nanodomain formation could be sensitively changed by Zr/Ti ratio of the grains in the ceramics.

Promising techniques are those which can combine high resolution analysis of plastic deformation marks and large areas of analysis with a high number of grains at different locations of the specimen without destroying the specimen.
Vignal et al. [3] obtained fine results using nanoindentation and point grids deposited by electron beam lithography as tools for the measurements of matter displacement but the number of grains investigated was small.
Their length was in general close to the grain size and they crossed while changing their direction the thermal twins embedded in a grain.
It consists first, from the AFM micrographs, in an accurate counting of the slip bands in each phase as a function of the plastic strain (Fig. 6). 0 500 1000 1500 0.2 0.7 1.15 1.8 Ferrite F Ferrite A Austenite Number of slip bands Macroscopic plastic strain (%) 0 50 100 150 200 250 300 350 400 0 0.5 1 1.5 2 Ferrite (type F bands) Ferrite (type A bands) Ferrite (total) Macroscopic plastic strain (%) Number of bands Number of bands Number of bands Number of bands Figure 6: Number of different slip bands in each phase of the duplex steel according to the imposed plastic strain Figure 7: Evolution of the number slip bands in the ferrite phase according to the slip band type (A and F) and as a function of the plastic strain In both the austenite and ferrite phases, the number of slip bands increases with increasing plastic deformation up to εp = 1.15 % and then decreases.
A linear increase of the number of type F slip bands is observed but an evolution of the number of type A slip bands similar to what occurred in austenite is noted, an increase followed by a decrease.

High grain density of diamond tool can be obtained.
The MBD type diamond grains were grit size of 140/170.
Diamond grain numbers per unit area were computed as grain density.
During grinding processes, grains could not be easily pulled out and high grain density of diamond tool was keeping.
During the buildup operations, ultrasonic agitation can compact grains and guarantee the nice contact between substrate and grains.

It is indicated that the average Nusselt number showing an undershoot during the transient period and that the time needed to reach the steady state is longer for low Rayleigh number and shorter for high Rayleigh number.
This interest was estimated due to many applications in, for example, packed sphere beds, high performance insulation for buildings, chemical catalytic reactors, grain storage and such geophysical problems as frost heave.
Variation of the transient average Nusselt number with s at different Rayleigh number.
This variation of the transient local Nusselt number is reflected on the average Nusselt number.
Fig. 4 shows the variation of the average Nusselt number with the dimensionless time for different Rayleigh numbers.