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It can be seen from the picture that there is crystal phase precipitation in the glass ceramic sample S1, but the grain is smaller and the number is less.
In the sample S2, the grain number and size increases.
The grain number of sample S3 increases obviously, and occurs grain reunion phenomenon.
As can be seen from Figure 3, with the increase of holding time, the degree of crystallization increases gradually, and the grain size and number also increase.
The transmittance of sample S4 is the lowest, with the increase of holding time, the grain size and number is large, and the grain reunion phenomenon is obvious, so the scattering degree of the beam is the biggest.

There are studies[6,7] pointing out that M/A constituents with different morphology could strengthen the microstructure, but meanwhile they destroyed the continuity of base metal, and compared with blocky M/A, long-bar or angular M/A would dissever base metal and cause a certain number of lattice distortion, which deteriorated impact toughness.
By the statistics and analysis of grain size in simulated CGHAZ under different heat input, the results indicate that as heat input increases (from 6KJ/cm to 30KJ/cm), mean grain sizes in CGHAZ of 1# steel are respectively 39.8μm, 40.2μm, 40.1μm, 44.3μm, 44.8μm and 45.7μm, and mean size of original austenite grains has little increase; mean grain sizes in CGHAZ of 2# steel are respectively 30.6μm, 33.8μm, 44.7μm, 45.5μm, 56μm and 69.8μm, and mean size of original austenite grains has obvious increase, especially when heat input is higher than 20KJ/cm, it is found by the further combination with microstructure characteristics that mean grain size rises obviously after 30KJ/cm which is more than twice the size of 6KJ/cm.
What’s more, austenite grains are variable in size and there are small grains among big ones, which indicate the increase of heat input worsens both microstructure uniformity and toughness [8].
High alloy content inhibits the growth of austenite grains.
Microstructure of 1# steel is mainly composed of granular bainite, bainite ferrite and M/A, and the grains are fine.

The measured resistivity is influenced by a number of microstructural factors such as the precipitate size and the volume fraction, the vacancy concentration, the concentration of solute in the matrix etc. [6].
Grain size analysis was conducted by the line intercept method.
Grain size corresponding to each heat-treatment case was obtained as an average from multiple specimens.
A LEO 1530 scanning electron microscope was used for examining sub-grain microstructural features.
The average grain size post-vacancy stabilization at 1045°C increased by not more than 15% of the as-solution-treated grain sizes.

We provide the expression for defining averaged values of the coordination number of the granule.
However, the employed media-loadings are composed both of commeasurable as well as multi-dimensional granules and/or grains.
It stands to reason to lay the value of the packaging density γ or porosity ω (and the coordination number of the ball value N connected with those parameters) as a basis for evaluating the model structure of the media-loadings of granules (grains).
Moreover, in keeping with similar, experimentally obtained values of γ and ω for other media-loadings (not purely ball-like granules or grains), their structures can be also considered as the closest to the ordered one for the balls with square-rhombic cells.
We also obtained an expression to define averaged values of the granule coordination number.

Since nonlinearity of the ZnO varistors is considered to originate in grain boundary, the electrical properties can be controlled by doping or changing the grain size and the thickness of the devices.
The calculated grain size of ZnO film was about 39.6nm.
ZnO varistor is a polycrystalline semiconductor containing a large number of grain boundaries.
The varistor voltage (V1mA) is closely related to the number of grain boundaries, the less the number of grain boundaries, the lower the varistor voltage (V1mA).
Based on the experimental results in this work, it can be concluded that the ZnO-based ceramic films prepared by rf magnetron sputtering contain a large number of grain boundaries, leading to the formation of the high Schottky potential barriers.

The effect of grain size on the mechanical properties of metals and alloys has been recently used in producing ultrafine grained microstructures reaching to enhanced strength and high hardness and wear resistance [1, 2].
Addition of MWCNTs developed grain refinement by the FSP and grain size less than 500 nm was obtained [10].
Grains in the side thermo-mechanically affected zone (TMAZ) are similar to the grains of base metal.
Grains in this zone are very small (with the grain size of ~7 µm).
Because the higher the volume fraction of particles, the higher the number of particles, the more the nucleation sites during recrystallization and the higher the pinning effect.

Although the synthesis of high purity alumina powders has been successfully achieved in a large number of publications, the consolidations of powders to full or nearly full density without appreciable grain growth are still a practical challenge[7].
The samples with an average grain size around 500 nm were obtained, which had a relative small grain growth compared with the precursor powders adopted.
In the TSS method, the sintering proceeds at low temperatures, which may keep the grain-boundary diffusion active but suppress the grain-boundary migration, for the grain-boundary migration has a higher activation energy than the grain-boundary diffusion [42].
A full-dense structure with the grain size of ~500 nm was achieved, a remarkable decrease in grain size were achieved compared with that of samples produced by conventional sintering[45].
It was proved that under very low vacuum pressure, oxygen partial pressure could deplete the diffusion from the contracting grain to the expanded grain[47].

As showed in Fig.3 (a), a large number of fine precipitates with the dimension of several nanometers dispersed in the matrix.
Firstly, the grain size of raw materials is the premise to ensure the size of grain and favorable texture of hot-rolled steel and cold rolled steel plate.
In this study, C and Mn steel are the main alloying elements, by adding these two elements, a large number of carbonitride precipitated in Iron.
Secondly, precipitates during annealing process restrict the grain boundary to move and restrain grain growth excessively, playing the role of grain refinement.
With an increase of the coiling holding time, the number of precipitates grows.

Effect of the Grain Size of Sand on Expansive Soil Yahya K.
Grain size of the Bentonite/Sand soil mixture.
The grain size distribution was conducted according to the ASTM (D421- 85-1972 and D422- 63-1972).
The maximum reduction in swelling percentages was obtained from D40 soil; on the other hand, the fine grain sand (sieve No. 200) gave inverse results with the highest swelling percentage in compared with other grain size of sand used (see Fig. 5).
The soil D200 had the lowest surface area among all the soils because of the minimum numbers of bentonite particles being replaced by sand particles.

SEM of fractured cross sectional portion showed that smaller grains were formed in case of microwave sintering.
Average grain size was calculated using linear intercept method and calculated value of average grain size and porosity of the samples are given in table1.
From this table it is observed that the grain size increases with increase in sintering temperature for both cases.
That can be attributed to low grain size in microwave sintered samples because smaller the grain size larger number of grain boundaries which resist the movement of electrons hence increase the resistivity9.
SEM of fractured cross sectional portion showed that finer grains were formed in case of microwave sintering.