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Diamond has a high hydrophobicity, poor shuirun moist, and small diamond grains are often contaminated in the grinding process.
At last, the powder grains were screened and the size of diamond particles was less than 3 μm.
It indicates that the diamond powder grains distribute evenly in the plating coating plated under the certain content of the selected dispersant.
And the diamond powder grains distribute homogeneously in plating solution which is stable.
It indicates that the wear-resisting is improved greatly because of a small number of diamond powder deposition.

The spherical LiFePO4/C particles consisted of a number of smaller grains.
The obtained spherical LiFePO4/C material constructed by grains exhibited good wettability and good electrochemical properties attributed to its uniform spherical structure.
And the spherical particles are consisted of a mass of LiFePO4/C grains, which are ~300 nm of diameter, as showed in Fig.2c.
(1) where A is the surface area of the cathode material, n is electron number for each molecule during Li ion insertion, F is the Faraday constant, C is Li ion concentration and σ is the Warburg coefficient.

Hence, each of the surrounding ferrite grains was a possible mother orientation i.e., more than one grain had to be considered as origin of an austenite grain.
The orientation of mother grains of a newly formed austenite grain was transformed according to the various orientation relationship models.
This leads to a stronger texture because Measured disorientation between bcc and fcc K-S N-W B 1 3 5 7 9 11 13 15 17 19 21 23 25 0 10 20 30 Number Variants some orientations are preferentially generated compared to others.
Influence of growth selection and grain boundary character.
To investigate the influence of grain boundaries on the nucleation of austenite the disorientation of all ferrite grain boundaries was compared with the disorientation of the ferrite grain boundaries where austenite was nucleated. 0 10 20 30 40 50 60 70 0.00 0.01 0.02 0.03 0.04 grain boundaries (fcc-nucl.)

The numbers on the micrographs refer to positions where EDX measurements were performed.
The same trend in the adjacent grain is observed, which confirms that the aGB grows into both grains in the present case.
To explain the growth of aWGB colonies into only one of the b grain, the crystallographic orientation of the two adjacent b grains and a phase was examined.
Close examination reveals that aGB and aWGB are in Burgers OR with b1 grain and not with b2. b-b grain boundary misorientation is close to 37° <23 16 -11>.
Fig. 4: Bright field image (a), SAD patterns and associated orientations for the sample annealed at 710°C for 10 min: b) b1 grain; c) aGB and aWGB morphology; d) b2 grain.

That is mainly to control the solid solution of the favorable inclusion,such as MnS and AlN, when heating in the heating furnace, and control the anew precipitation process of the inclusions with tiny, diffused, a certain shape and number.
If the heating temperature is too high, the slab is easy to generate horizontal crack, the product is easy to appear linear fine grain and the magnetic go bad.
Due to adopt ong-time cold rolled method, the grain size of S20 and S23 in the product is smaller, the regulated heating temperature of slab was 1180˚C± 20.
The high heating temperature of slab would produce some tiny inclusion which was disadvantageous to the grain growth in the hot rolled steel plate, but adopting critical deformation method at final, which could guarantee the grains be coarse, and the iron loss meet the requirements.
This would not hinder the grain growth.

The crack is initiated from the grain boundary boride as demonstrated by arrows in Fig. 3(b).
For the specimen brazed at 1200 oC for 1800 s, grains of the brazed joint is distorted (Fig. 3(c)), and a few grain boundary borides are fractured as indicated by arrows in Fig. 3(d).
The brazed joint mainly comprised of grain boundary borides and Cr/Fe/Ni-rich matrix.
The Cr/Fe/Ni-rich matrix is ductile as compared with grain boundary borides.
Acknowledgements Authors gratefully acknowledge the financial support of this research by National Science Council, Taiwan (Contract number NSC 102-2221-E-002-148).

The higher the temperature, the larger is the grain size.
The ceramics with the smaller grain sizes (HP) are harder but less tough than those with larger grain sizes (PS), Fig. 3.
Above the percolation threshold, grain coalescence also takes place.
The higher temperature and longer times in the PS method induces a larger grain size of the β-Si3N4 grains with different intergranular crystallinity relatively to HP samples.
Almeida's work is supported by Programme Alβan, European Union Program of High Level Scholarships for Latin America, identification number E03D06378BR.

The grinding temperature field model The interaction between abrasive grains of grinding wheel and work-pieces in grinding process is very complicated, so it is difficult to accurately measure and analyze the force on each grain and heat dispersion.
During the grinding process of zirconia ceramics, the distribution of the abrasive grains on the surface of grinding wheel was irregularly, so it was difficult to analyze and calculate the grinding force of a single grain.
（5） Where: kg is the thermal conductivity of grain; r0 is effective contact radius of the grain (r0 = 15μm is the value of effective contact radius for typical grains); (kρc)w0.5 is the coefficient of the contacts between work-piece materials.
Then the model was divided into a finite number of independent units, in which the material properties of each unit cell could be defined to load moving loads, and finally, calculation of equation was conduction and the results are analyzed.
Due to the contact friction between the grains in the front part of grinding wheel and the work-piece, high energy might gather on the top of the grains.

Different grain boundary morphologies, such as well-interlocked, planar, and mixed grain boundaries, are observed (see arrows in Fig. 1a).
Previous study indicated that grain boundary morphology depends on cooling rate [13].
Even in the unaged condition, β particles are present at lamellar colony boundaries and the number of particles increases significantly during aging as shown in Fig. 1b (see white arrows).
As illustrated in Fig. 3a and b, this alloy exhibits dendritic columnar grains with a primary dendrite arm spacing of approximately 300 µm.
Coarse β particles and silicides are observed along the columnar grain boundaries and within the grains.

Pulsed current resulted in better grain refinement and the same is reflected in the microhardness values.
In conventional GTAW welding, fusion zones typically exhibit coarse columnar grains and results in inferior weld mechanical properties [4].
A number of trial runs on the base material were done to fix the upper and lower heat input levels.
This may be due to the refinement in fusion grain size by PCTIG weld.
[6] Kou S, Le Y, 1986, Nucleation mechanism and grain refining of weld metal, Welding Journal, Vol. 65, pp. 305-313