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Adding porosity to polycrystalline magneticshape memory alloys presents solutions for (i) the elimination of grain boundaries via the separation of neighboring grains by pores, and (ii) the reduction of production cost via replacing the directional solidification crystal growth process by conventional casting.
Due to constraints imposed by grain boundaries, the MFIS is near zero in randomly textured, fine-grained, polycrystalline Ni-Mn-Ga [6].
Foam I with 0.12% MFIS was cast from an alloy with composition Ni50.6Mn28Ga21.4 (numbers indicate atomic percent).
Some thick struts and nodes, however, have multivariant twin structures and even grain boundaries (Fig. 2a).
This strain, however, is much smaller than the MFIS of foam II with bimodal grain size distribution.

The number of domains is set with consideration of computational speed and efficiency.
It could be seen that no stray grains were observed in sections II in both castings A-3 and B-3.
That means the grain selectors functioned well at the withdrawal rate 7.0mm/min.
In casting A-3, we could see stray grains formed at platform in both simulation results and real blade casting, while in casting B-3 no strain grains were observed in the platform.
The stray grains occured at the platform of all the three blade castings at uniform withdrawal rate 7.0mm/min.

However the price of palladium is too high, which causes a serious pressure for the MLCC production, especially when the number of dielectric layers rapidly increases today [1].
In another aspects, the increasing of dielectric layer number requires diminish of the layer thickness, in turn, the particle size of the powders used for the dielectric ceramic layers in MLCC.
The grain size of specimens sintered at 1200℃ was examined by scanning electron microscope (SEM S250-MK3).
It means upon the increase of temperature, the grain size in the samples has been increased.
The grains in Fig.3 have a rather round shape, hence a lower density of the ceramic.

The grain size of electrodeposits can be controlled using pulse plating [5] and additives [6].
When TC of any (hkl) plane is larger than unity, a texture exists in which grains are oriented with their (hkl) planes parallel to the surface.
It is the additive which inhibits grain growth.
Because, the deposit of Fig. 2 (c) was obtained at the high temperature of 80°C, grains must be large and have a high dislocation density, despite the additive and the pulse plating which tend to reduce grain size.
The Ni electrodeposits using the AD and the AS methods showed the nanocrystalline grain size. 3.

These models employed equations published in the literature describing kinetics of softening, grain size evolution and grain growth.
All numbers are in % weight.
Surfaces 0.3 mm in depth maximum were polished and etched using teepol and nital 3% so as to reveal the evolution of austenite grain size and measure final ferrite grain sizes by counting at least 200 grains.
Table 2 shows grain sizes measured from the samples.
Grain growth between CMM and SRM.

So the fracture mechanism of SiCp/AZ91 composites is altered by extrusion because the segregation of particles and defects in the grain boundaries are largely eliminated by extrusion.
As can be seen in Fig. 1(a), there are no clusters of reinforcements, but the most of SiCp distribute in the grain boundaries which are masked by the large Mg17Al12 phase.
Compared to the as-cast composites, the matrix alloy of the extruded composites has undergone much more plastic deformation, as there are a large number of dimples in the matrix in Fig. 3(a).
It can also destroy the old grain boundaries and new grain boundaries are formed by recrystallization [15, 16].
Extrusion can also increase the dislocation density and decrease the grain size [6, 11, 12].

For example, in catalytic applications, compared to conventional grain size (or µm) magnesium oxide, nanophase grain size magnesium oxide adsorbed up to ten times more organophosphorous and chlorocarbons [27].
It was speculated that nanophase compared to conventional grain size magnesium oxide increased adsorption of these species due to greater numbers of atoms at the surface, a higher surface area, increased grain boundaries at the surface, and less acidic OH- groups (due to a much larger proportion of edge sites for the nanophase magnesium oxide to cause delocalization of electrons; Fig. 1) [27].
(a) Conventional or micron grain material (b) Nanophase or nanometer grain material Fig. 1: Difference in Surface Properties of Conventional Compared to Nanometer Alumina Surfaces.
In this respect, nanophase materials that, by their very nature, possess greater numbers of atoms at the surface, higher surface areas, larger portions of surface defects (such as edge/corner sites), increased electron delocalization, and greater numbers of grain boundaries at the surface have an advantage over conventional larger grain size materials for many biological applications.
While a number of investigators have demonstrated increased tissue growth on nanophase materials, how such novel nanophase materials will be incorporated into the next-generation more effective biomaterials remains to be seen.

Result of EDS shown in Fig.6 proves that elongated grains contains only N and Si elements is pure Si3N4 grains.
It was reported that elongated β-grains are commonly developed in the sintered Si3N4 ceramics because the growth of β-grain is anisotropic with the c-axis growth rates generally exceeding those normal to the prism faces [6].
A lot of elongated grains dropped off from the surface leaving some pits and large island steps.
There are also some pull-out and cracked grains on the surface.
Y2O3 aid can facilitate the growth of β-Si3N4 grains and result in a higher average aspect ratio and a reduced number of grains per unit volume [8].

The morphology of the grains in BBT thin films is spheroidal and the grain size is about 120nm.
Many researches have been conducted on their anisotropic properties in grain-oriented polycrystalline, block and thin films [7-9].
The morphology of the grains in BBT thin films is spheroidal.
The growth of crystal grain is smooth and uniform, and the grain size is about 120nm.
The morphology of the grains in BBT thin films is spheroidal and the grain size is about 120nm.

Besides, for the NCD, it is a thin film grown with grains smaller than 100 nm and low to moderate amounts of sp2-bonded carbon trapped at defects or grain boundaries.
The films grown during 6 and 10h presented a uniform morphology with ultrananocrystalline grains as shown in Figs. 1a-d.
Bernard et al. [7] have suggested that the 500 cm-1 band is assigned to the increase in the number of boron pairs.
Graphic of the number of acceptor densities of all films calculate from Raman spectra as a function of boron doping levels for three growth times.
Graphic of the number of acceptor densities of all films calculate from MSP as a function of boron doping levels for three growth times.