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The grain size of the Ni-20Cr-1.2Y2O3 alloy is considerably larger than that of Ni-20Cr alloy.
The average grain size of the Ni-20Cr-1.2Y2O3 alloy was measured to be 130 nm while that of the Ni-20Cr alloy was about 630 nm.
The effect of Y2O3 addition on the grain size is clearly evident.
The fine and stable particles were crucial for retaining a much finer grain size in the Ni-20Cr-1.2Y2O3 alloy.
A number of characterization techniques (XRD, SEM/EDS and TEM) were used to characterize the ball milled powder.

One way to increase low-temperature ductility is to reduce grain size.
However, alloys with a fine-grained structure have a reduced creep resistance.
Experimental data can be used to simulate the sintering process of powder material Contact and Sintering Behavior To calculate a large number of particles, and in particular for sintering processes, the discrete element method is used.
Gusev, Investigation of nanostructuring processes in fine-grained concretes with silicon dioxide nanoparticles admixture, Nanotechnologies in construction 3 (2009) 8-14
Johnson, New method of obtaining volume, grain boundary, and surface diffusion coefficients from sintering data, Journal of Applied Physics 40 (1969) 192-200

XRD analysis was used to measure the grain size and phase compositions of NASICON disc.
Densification and grain growth are probably associated to a liquid phase produced in sintering process [27].
Table 1 Grain size, density, conductivity at 250°C and active energy for different disks.
The increase in conductivity when increasing sintering temperature could be ascribed to decrease in grain boundary density, resulting from both increasing sample density and grain size.
The slope of the sensor is about 82.9 mV/decade, and the number of the reaction electronics is about 2.08 at 450°C.

Ni-TiN nano composite coating (Fig. 3) has flatter surface, smaller grains, homogenous distribution of TiN, and compact structure.
Preparation of nano composite coating Ni-TiN composite coating is composed of TiN nanoparticles and the matrix metal Ni with pulse electrodeposition, composite volume of the nanoparticles can be controlled effectively through design and process, thus improve coating electrical erosion resistant ability, the reasons are as follows: (1) TiN nanoparticles interfered electrodeposition process of Ni, and prevented grain growth, aggregation and grow up, to the refining effect on metal grain up in codeposition process of nanoparticles and the matrix metal.
At the same time, the TiN particles mainly exist at the grain boundary in the hard phase particles, can be pinning the grain boundaries and grain refinement effect, improve the lubrication effect of adhesive coating and Cu radical, reducing with the surface of the internal stress, thereby enhancing the coating resistance to electrical erosion resistance. (2) Nano composite grain quantity can be effectively controlled by changing the TiN particles content.
Surface base material Cu through discharge to complete the material erosion, after many times of pulse discharge, the end has an approximately inner concave, and Cu has a large number of loss, TiN particles in the coating will be protruding and remained at the electrode surface, eventually forming a tiny tip.

In this case ϕi with i =1,…, N describes the distribution of each phase in space and time, where ϕi is 1 inside the grain and 0 elsewhere.
Between two grains i and j, at the interface, ϕi + ϕj =1.
Each grain or domain is distinct from others by phase and it has its individual phase field variable ϕα.
The plasticity in metals is due to the motion of the dislocations and grain boundaries.
The shape of the cementite is lamellar and not needle-like at the tip of the grain.

However, since the castability of this alloy is very poor, so under normal circumstances it is unsuitable for some conventional casting process such as metal casting, low pressure casting and high pressure casting because of the existence of such defects as coarse grains, inhomogeneity and composition segregation and so on which decrease mechanical properties, integrity, and reliability of the products [7, 8].
With the increase of the applied forging pressure, the microstructure has a significant change in the grain size and uniformity.
When the applied forging pressure was more than 120 MPa, the microstructure of the alloy consisted of a large number of fine equiaxed grains and the uniformity of the microstructure was greatly improved, the grains were refined obviously because of the forging pressure (as shown in Fig.5e and f ), which can be clearly characterized from the Fig7.
The microvoids nucleate in material at the areas of localized high plastic deformation such as that associated with second phase particles, inclusions, and grain boundaries.
Mechanisms for grain refinement of Mg alloys by superheating [J].

The increased W content to the power was simply due to the increased number of atoms or molecules ejected from the W target [7].
It was originated from the good crystallization caused by increased grain size or the residual stress induced in the crystal lattice.
The grain size was estimated by the FWHM of the diffraction peaks as listed in Table 3.
The Cr-W-B-N coating exhibited a fine-grained dense columnar structure and more dense than Cr-B-N coating.
It was found that the grain size become coarsening as adding W into Cr-B-N coatings.

This allows CUDA program to handle the fine-grained and coarse-grained data parallelism flexibly.
The number of threads is the same as the number of GPUs in the system.
GN is the GPU number.
From the figure, the near linear speedup can be obtain with the number of the GPUs.
It can achieve almost linear speed up according to the number of GPUs in the system.

The analysis results for the microstructure indicate that grain size of C3S in the samples with MoO3 is larger than that of only -portland clinker.
Grain growth rate is more quickly than the nucleation rate, which promote large crystal formation of C3S.
Therefore, Changing the nature of liquid phase by admixture influence on the nucleation and growth rates of C3S, which result in the number and size of the grain of C3S difference.

The microstructure observed from SEM analysis was in line with the density obtained as the surface of sintered compacts synthesized in water medium (M1) contained less pores with large grain growth.
Hydroxyapatite (HA) is usually used for a number of biomedical applications in the forms of granules, blocks, coatings and dense bodies [2-5].
The large grain growth with coalesced particles arranged in more dense structure can be seen prominently in sintered compacts of M1.
The grain growth with more dense structure was exhibited by sintered compacts of M1 which also in agreement with the relative density obtained.