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Similarly average grain size of Ni become about 8 nm after the aging at 473 K.
After the aging at 573 K, average grain size of Ni became about 6 nm, indicating that grain size did not grow.
Both of them were comparable in grain size and consituted two-phase structure.
Grain size distribution of Ni3P cannot be evaluated because of limited number of grains in the micrograph.
There is a grain with strong intensity of P, but solute P is not segregated at the grain boundary.

The growth orientation of grains also changed with the number of spin-coating cycles.
With the increase of spin-coating number, the proportion of Se atoms decreases, resulting in a transition to a sulfur-rich state and thereby causing a shift towards an increased diffraction angle [16,17], and also promoting the growth of Sb2S3 grains.
As the number of spin coating increased to three and four, the grains in the film grew, yet the surface morphology deteriorated.
The grain size of the thin film gradually grew.
Acik, Analysis of grain orientation and defects in Sb2Se3 solar cells fabricated by close-spaced sublimation.

With heating-cooling times increase, the grain size and shape of the primary Si decrease.
The latent heat method of storage has attracted a large number of applications, as will be discussed in this review paper.
The grain size of α-Al phase increases and the number of the crystal α-Al grain decreases with the heating-cooling cycles increase.
In addition, the bigger grains lead to decrease of grain boundary area.
It could be conluded that the shape of primary and eutectic Si phases, the the grain size of α-Al phase increases and the number of the crystal α-Al grain decreases might lead to the latent heat of Al-Si alloy decrease.

Due to the large number of solutes and wide solidification temperature range of 7075 aluminum alloy, dendrite non-equilibrium eutectic microstructure will produced during solidification.
The second phase along grain boundaries contained 61.36wt.% Al, 20.24 Zn, 9.99 Mg, and 8.41 Cu.
In the as-cast morphology, a large number of Mg (Zn, Cu, A1)2 phases were connected along the grain boundary.
Al2CuMg Fig. 6 EDS analysis of non-equilibrium eutectic structure of 7075 Al alloys Fig. 7 X-ray diffraction pattern of 7075 Al alloys Because of the first-order homogenization, there are still a large number of coarse non-equilibrium eutectic phases along the grain boundary.
There have still been some coarse Mg (Zn, Cu, Al)2 phases along grain boundaries.

On the other hand, the PV sample with 35μm of grain size showed a higher breakdown voltage compared to that of the conventional alumina with the same grain size.
Table 1 Grain size and fracture toughness of the dense alumina materials Figure 4 shows change of thermal conductivity of the alumina samples with grain size.
While the number of grain boundaries of the conventional alumina with grain size 10μm was 380 units/mm, the number of boundaries of the PV and PP samples decreased to 92 and 39 units/mm, respectively.
This reason was thought that the PV sample had higher mechanical properties, but grain size was not so small: 12μm, as shown in Fig.4 and the number of grain boundary was not so large: 92 unit/mm.
Furthermore, the grain boundary between anisotropic grains with match lattice plane seemed not to have a high barrier of the heat conduction.

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.

In some grains two twin variants were observed.
Inspection of the grain orientations reveals that some grains are in fact fully re-oriented by twinning after a compression of 10%.
Examples are given for two grains in Table 1.
Analysis of a larger number of grains is therefore currently underway to see if these observations also apply to the deformation of AZ31.
In some cases grains are fully twinned.

Spherical and more uniform tungsten grains distribute in matrix phase in 85W alloys with Ni:Cu ratio of 1:1 than that of 3:7 and 7:3.
Contiguity（CSS） defined as the relative fraction of W-W interfacial area was determined by counting the number of W-W(NSS) and W-M (NSL) intercepts in unit area and calculated by the formula[7] as: CSS = 2NSS / (2NSS + NSL).
The corresponding tungsten grain sizes and CSS values are shown in Table 1.
At lower tungsten content, volume fraction of matrix phase is larger which leads to tungsten atoms fully solving in liquid matrix and then re-precipitation on solid tungsten particles, however, lower tungsten content make total tungsten atom number of solution-re-precipitation reduce.
Table 1 Grain size and CSS of the investigated tungsten heavy alloys 85A 85B 85C 80B 88B Grain size (μm) 27 28 27 23 31 CSS 0.35 0.36 0.36 0.22 0.43 1.2 Ni:Cu ratio effect on microstructure W particles shown in Fig. 1b are more spherical and uniform than those in Fig. 1d and Fig. 1e.

Severe plastic deformation (SPD) is employed to produce Ultrafine Grained (UFG) structures.
Titanium sponge showed decreased grain size and porosity with increasing backpressure.
Over a decade, a large number of processes are being developed to reduce the cost and increase its applications [2].
On the other hand, the sample consolidated with 150 MPa back pressure showed a large number of small grains when compared to the sample consolidated by 100 MPa.
Horita, Using equal-channel angular pressing for refining grain size, J.

In the two-step annealed Zr-1Nb-0.12O tubes, dislocation-free recrystallized grains with a larger grain size than regularly annealed Zr-1Nb-0.12O tubes.
Creep life has been suggested to increase with increase of grain size because the contribution of the fast diffusion along grain boundaries decreases.
However, other studies have indicated that the creep rate may increase or decrease with decreasing grain size, or be grain size-insensitive in copper [6].
Both models suggest that the effect of grain size varies with experimental temperature and conditions even in identical materials and the dislocation activity near-grain-boundary regions could increase the creep rate in the small grain size region, supporting the decrease of creep rate with increase of grain size in the present study.
In general, with the increase of temperature, the number and mobility of thermal vacancies increase, causing more vacancies or impurities to diffuse to grain boundaries.