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Grains and distribution of elements in dielectric layers were observed by TEM-EDS.
(a) (b) Dielectric layer Internalelectrode Internal electrodeelements were located around grains.
In sample A, Y elements probably didn't diffuse into grains easily because BaTiO3 had high tetragonality.
However, in sample B, Y element diffused all over grains because of low tetragonality of BaTiO3.
Relationships between temperature and relative dielectric constant and dielectric grains were analyzed.

Severe plastic deformation (SPD) is used to convert traditional coarse grain metals and alloys into ultrafine-grained (UFG) materials.
UFG materials possess a number of improved mechanical and physical properties which destine them for a wide commercial use.
SPD causes the creation of micrometer and sub-micrometer sized subgrains in the original coarse grains of the material.
Sufficiently large deformation leads to a distinct structure of dislocation-free and highly misoriented fine grains.
It can be achieved by increasing the rolling temperature which, however, cannot be too high to avoid grain growth.

A large number of fine acicular ferrite in HAZ can ensure that the welding plate has high strength and good low temperature impact toughness.
Molybdenum was prone to assemble on the grain boundaries, hence would hinder grain boundary movement and enhance the strength of steel[15].
The differences of the microstructure and grain size are one of the main factors causing performance difference, the retained austenite or M-A island would deteriorate the impact toughness, while, grain refinement can improve simultaneously the strength and toughness.
In general, in order to gain good impact toughness of HAZ, fine acicular ferrite and the least amount of coarse-grain phase in HAZ are expected.
A large number of fine acicular ferrite in HAZ can ensure that HAZ has high strength and good low temperature impact toughness.

A large number of rare-earth-containing glasses have been developed for various applications involving laser, Faraday rotator and optical lenses with high refractive index [3].
Both doped aluminas have a noticeably finer grain structure and higher porosity; the dopant appears to retard grain growth during sintering.
The lanthanum doped Al2O3 sample was nearly fully dense with finer grain structure and grains with higher aspect ratio than the aspect ratio of alumina grains of the yttrium doped sample (Fig. 1c).
This segregation effectively hinders abnormal grain growth of alumina.The increase of fracture toughness can be ascribed probably to the presence of elongated alumina grains and particles of second phase at alumina grain boundaries.
No influence of dopants on hardness of LPS aluminas was observed.AcknowledgementFinancial support of 2003 SO 51/03R 06 00/03R 06 03, the Slovak National Grant Agency VEGA under contract numbers VEGA 2/4072/24, 2/3101/23, and CE NANOSMART, is gratefully acknowledged.References [1] J.

In the annealed films, these cauliflowers separated some small grains, decreasing the film thickness.
SnO2 thin films have been fabricated by a number of techniques, including spray pyrolysis [3], sputtering [4], chemical vapor deposition (CVD) [5], thermal oxidation [6], and so on.
The grain size was measured under 10 nm.
Grains and grain boundaries were more clearly observed in the films deposited for 30 min than for 5 min.
The decrease of grain diameter was also happened after post-annealing, resulting from separating cauliflower-like grains to individual particles and thermal shrinkage.

It indicates that the Mg2Si phase cannot compensate for the adverse effect of grain growth.
The method of keeping fine grains of as-SLMed AlSi10Mg alloys treated with heat treatment is rarely reported.
Number As-SLMed T4 T6 T1 Process / 540°C × 2 h water cooling 540°C × 2 h water cooling + 180°C × 4 h air cooling 180°C × 4 h air cooling After polishing, the surfaces of samples were etched with a solution of 10 vol.% hydrofluoric acid (HF) in 90 vol.% H2O at 15 seconds.
The increase of α-Al and Si grain size results in a decrease of microhardness.
During the solution treatment, the formation of the β-AlFeSi phase and the grains grow up quickly.

It is generally considered that the grains of a well-dressed wheel will protrude by half the grain size.
In Fig. 3, it can be observed that many grains are embedded in the diamond wheel.
By comparing Fig. 4 and Fig. 5, it can be seen that the laser-conditioned diamond wheel surface has greater numbers of protruding grains than the diamond wheel surface dressed using the #6000 cup truer.
The numbers of grains were counted in these SEM Table 2 Experimental conditions Wavelength 355nm(UV3) Pulse frequency 50Hz Number of laser iradiation 1�3 times Laser energy density 1.1�23.9J/cm2 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 0.0 5.0 10.0 15.0 20.0 25.0 Laser energy dencity�J/cm 2 Ablation depth�µ� �U�QV �U�QV �U�QV 0 W� DGT�QH��CUGT�TCF�CV�QP Fig. 2 Ablation depth of resinoid bond Table 3 Conditions of laser conditioning Wavelength 355nm(UV3) Pulse frequency 50Hz Spot size of laser focus beam 50µmh50µm, 10µmh10µm Laser energy density (J/cm2) 1.1 1.9 3.7 6.2 9.3 12.5 Number of laser radiation 13 10 7 5 5 4 Grinding wheel SD1500B125 images.
The cutting edge density, defined as the number of grains per unit area, was determined by dividing the number of counted grains by the area of the SEM images.

And the aspect ratio of tungsten grains increases along the axial direction in the swaged alloys.
The aspect ratio of tungsten grains (C) is obtained according to the following equation[11]: C=1ni=1nliai (1) where li is the long axis of the tungsten grain, ai is the short axis of the tungsten grain and n is the number of measured tungsten grain.
Tungsten grains are elongated along the axial direction after swaging.
(e) And the aspect ratio of tungsten grains of W-HEA with different amounts of reduction in area.
W grains around the surface exhibit a higher aspect ratio than that in the center.

However, the formability of magnesium alloy at low temperature is poor because of its hexagonal close-packed crystal structure, which leads to the insufficient number of operative slip system [1-3].
A number of investigations have been performed on the deformation behavior of wrought magnesium alloys[4-9].
Besides, most of the recrystallization grains formed along the prior grain boundaries resulted in the formation of necklace microstructure.
To reduce the stress concentration around grain boundaries, the accumulated dislocation rearranged to form low angle grain boundaries.
The misorientation of low grain boundaries increased with the increasing of strain, and thus some recrystallization grains formed along the orientation grain boundaries, as shown in Fig.5(a).

A number of parameters characterize these boundaries: � Misorientation angle � Rotation axis � Boundary plane � Boundary spacing � Boundary width � Macroscopic orientation A number of experimental techniques are now available for quantification of boundary parameters.
An example is shown in Fig. 4, illustrating microstructural observations of 82 grains in tensile strained aluminum (99.99% purity) with an original grain size of about 300 μm [9].
The structural classification has been related to the grain orientation by plotting the grain tensile axis in an inverse pole figure.
This figure shows a clear correlation with grains in the middle of the triangle developing Type 1 structure, grains near the [100] corner developing Type 2 structure and grains near the [111] corner developing type 3 microstructure.
Huang et al.: Ultrafine Grained Materials III, Eds.