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The power transfer characteristics of piezoelectric PZT (lead zirconate titanate) ceramics were studied by a number of researchers.
The micrographs have a polycrystalline texture, and grains are evenly dispersed throughout the samples with no or few spaces, indicating that the materials are dense.
For the selected compositions, unequal sized grains (3–12 μm) were identified, with the sizes decreasing as x increases.
The creation of tension, which limits grain boundary movement during sintering and consequently results in grain size reduction, could be ascribed to the reduction in grain size.
The grains sizes were found to decrease with increasing x which ranged between 3–12 μm.

As a result, a growing number of complex refractory ore resource with the characteristics of low-grade, fine particles and symbiotic complex come into ore dressing and metallurgy industry[1-3].
In order to study the grain size characteristics of the ferrum containing mineral in the tailing, sieving of the tailing and the chemical analysis of the grade of each size fraction are carried out, the result is shown in Table 2.
Therefore, we can conclude, the disseminated grain size of the ferrous containing minerals is very fine, only being milled to a finer fineness smaller than their disseminated grain size[4] , the ferrum containing minerals can be fully dissociated and can easily be dressed by the dressing equipment.

Introduction One of the most effective and the most studied ways to get ultrafine-grained structure of materials is equal channel angle pressing (ECAP).
In software complex DEFORM-3D, was built a number of finite element models with geometric parameters according to fig.1.
Thus, of all the discussed variants, the most favorable stress-strain state to produce ultrafine-grained structure provides option (B).
Conclusions From results of modeling is shown that the most favorable stress-strain state to produce ultrafine-grained structure provides option (B).

The influence of stress The inner stress will produce after the silicon steel plate being cut by press and piled up, crystalline grain will be distorted and magnetism conductance will drop.
Because the ordinary water contain a number of exiguity grain that cannot melt in water, such as calcium carbonate, manganese, iron, silicon dioxide and so on.
Not only these materials can reduce the life of the jet nozzle, but also influence the condensing ability of jet liquid, the result would be reduce the cut efficiency, so that these exiguity grain should be eliminated.

The strain scanning method with tilting oscillation was employed because of the large grain size of the OFC sample.
It is considered that the grain size of the TP1 sample with 10 cycles is smaller than that of the TP1 sample with 0 cycles because of recrystallization due to cyclic thermal deformation.
Fig. 4 shows the relationship between the number of cycles and residual strains for each reflection.
Further, residual strains become tensile when the number of cycles is more than 2.
Relationship between the number of cycles and the averaged residual strain.

It corresponds to the state when local stresses around pile ups of dislocations at obstacles, predominantly grain boudaries, start to obstruct magnetic domains in rotation to the direction of tensile macrostress.
This quantity varies with the number of stress cycles much as the MPL.
By plotting these changes against the number of stress cycles n diagrams L0 - n and MPL - n can be obtained.
Fig.3 represents the variation of L0 and MPL with the relative number of cycles n/N for push-pull loading of the specimens with the amplitude σa = 230 MPa and frequency 1 Hz.
Kobayashi and S.Takahashi, The Relation Between AC Permeability and Dislocation Density and Grain Size in Pure Iron, International Journal of Applied Electromagnetics and Mechanics, 25 (2007), pp. 341-346

CET occurs when equiaxed grains grow ahead of the dendrite tips in the undercooled liquid.
If their number and size are large enough, equiaxed grains can stop the columnar growth and form an equiaxed microstructure [5,6].
It is well known that equiaxed grains lead to more isotropic macroscopic properties and a more homogeneous composition field than columnar microstructure.
Depending on the application, one type of microstructure is preferred and thus favored e.g. equiaxed grains in casting industry of aluminum alloys and columnar grains in turbine blades.
Above 2g0, morphologies were fragmented and a great number of clusters of globular cells or dendrites are distributed in a cross section (Fig.5d).

One of these factors is the variety of geometry of the cutting grains, i.e. the abrasives in the honing tool, and the different displacement possibilities.
During processing, the interaction of abrasive grains with the surface becomes complicated, which makes it necessary to study more deeply the effect of honing process parameters on the quality and accuracy of the surface.
To determine πr180°φ, the number of burrs on the honing tool and the structural dimensions must be known.
The number of honing stones in standard honing tools varies from 3 to 12, depending on the diameter, degree of grain and brand (electrocorundum, silicon carbide).
It should be noted that the correct selection of the brand and the degree of granularity (grain) has not only mechanical but also chemical bases.

Bi-2223 superconductor samples were characterized by X-Ray Diffraction (XRD) using CuKα radiation in the range 2θ = 5−70° by (Shimadzu X-lab 6100) diffractometer, Field Emission Scanning Electron Microscopy (FESEM) was used to examine the surface morphology and grain structure of the samples, Energy-Dispersive Spectrometers (EDX) for detect the elements percentage inside samples and resistivity–temperature (R–T) measurements was measured by four-probe measurement system (HMS-5500) ECOPIA CORP cooled down from 300K to 70K to determine superconducting transition temperature of the prepared samples.
The number of thin rectangular grains increases, indicating the increase in the low-Tc Bi-2212 phase, voids, and hence porosity.
Furthermore, the number of spherical grains refers to the Ca2PbO4 non-superconducting phase increasing.
%,(c)x= 0.15wt.% and (d)x= 0.20wt.% The EDX spectra were done at the same grains of FESEM.
As 𝑥 increased the superconducting main phase grain size increased and the alignment of grains was affected and crystalline-size, determined from XRD investigation.

The Theory of Fatigue Analysis When the spare parts are under the circulating load, the microcrack could form in the grain whose local stress is the maximum or is the minimum.
It also can form in the maximum stress on the grain.
The parameters , and are respectively the number of fatigue cycling, the fatigue strength index, the elastic modulus of the material.
The number of specimen is 3, test result and fatigue failure picture is as shown in Table.1 and Fig.5.
According to the result of fatigue life finite element analysis of the sub-frame, the low fatigue life area presents on the control arm’s bracket, and the number of times a stress cycle is approximately 100000 cycles.