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The average size of augite grains in form of spherical particles is found within the range of 100-250nm.
A great number of spherical crystals in the range 100-250nm in diameter can be seen on the etched surface of the all three samples.
At the same time, the number of crystals of GC1 is the least.
That number increases slightly in GC2 sample.
GC3 sample has the most crystalline grains.

As a result, the number of trials for stamping, which are often quite expensive and timeconsuming, can be significantly reduced and consequently the development time for new models shortened.
One drawback of this approach is that it requires a significant number of mechanical tests to identify the parameters when a flexible yield function is used.
In realty, plastic deformation cannot be homogeneous due to grain boundaries and different orientations of each grain.
The crystal plasticity model can calculate the plastic work and the plastic stress of a grain with a given lattice orientation without any knowledge of the response of other grains if the velocity gradient tensor that describes this homogeneous plastic deformation is prescribed.
This approach is based on the physical aspects of plastic deformation and on averaging the response over a large number of grains.

Introduction The main purpose of second phase particles is to enhance the strength, grain refinement and effect hydrogen traps.
It can be found that the longer of etching time, the deeper of the grain corrosion.
It can be found that the number of small particles in the surface of 3 # sample is more than that of 2# sample.
Additionally, small particles cannot be eroded by nitric acid alcohol, therefore, small particles can only be observed after the samples are eroded, and the longer of corrosion time, the more of the number of small particles.

The evolution of plastic anisotropy and nonlinearity in a polycrystalline metal is linked to the plasticity-induced microstructural evolution that occurs commonly at least at two levels: the shape, size, and crystallographic texture evolution of crystalline grains and the dislocation substructure evolution within the grains.
Each flow surface of a heterogeneous polycrystal is the envelope of a large number of micromechanical flow sub-surfaces and is approximated by the sum of multiple homogenous stress terms.
The number of homogenous stress terms corresponds to the number of independent stress states realized in the mechanical tests at each fixed set of loading orientation angles and the number of orthogonal bases in the generalized spherical harmonics corresponds to the number of different sets of loading orientation angles realized in the mechanical tests at each stress state.
The suitable numbers of the homogenous stress terms and generalized spherical harmonic terms in a flow potential are determined by the nonlinearity and anisotropy of the plastic flow in a heterogeneous solid.
The polycrystal is a coldrolled and heat-treated AA5052-H32 aluminum sheet and its microtexture data were collected over more than 400 surface grains using the electron backscatter diffraction technique (EBSD).

Introduction With the high speed increasing of China's automobile number, the products of waste rubber and waste tire have also been increasing year by year.
Grain size was also an important factor.
Materials The raw material is grain of waste tire, and put them into the drying cabinet for 24h in 105℃ in order to remove the surface and inside water of grain.
Then cracked to obtain the grain of 100 mesh (about 0.15mm).
Grain size was about 0.15 mm.

It indicates that the applied sheath influences considerably the grain connectivity.
Therefore, the individual grains shown in Fig. 5 have not the same contrast.
Apparent is one structural difference showing very big (> 50 μm) MgB2 broken grain in ex-situ core in comparison to more uniform and smaller grain structure observed for in-situ one.
No cracked grains structure was found in the in-situ cores.
Acknowledgement This work was supported by the Science and Technology Assistance Agency APVT-51-029902, under the EU FP6 contract number NMP3-CT2004-505724 and by VEGA 2/5088/25.

According to Fig. 2(c), the W2B particles distributed homogeneously throughout the microstructure consist of grains ranging in size between 50-100 nm.
As seen from Figs. 4(a) and (b), micron- and submicron-scale TiB2 particles (dark color) located both at grain boundaries and at grain interiors in W1Ni matrix (light color) have a homogenous distribution throughout the microstructure.
The microhardness values of the W1Ni-2TiB2 samples increased gradually with increasing MA duration as a result of increasing relative density and grain refinement during MA.
Acknowledgement The authors would like to express their appreciations to the Scientific and Technological Research Council of Turkey (TUBITAK) for funding the project with the number of 110M130.
Yoon, Activated sintering of nickel-doped tungsten: approach by grain boundary structural transition, Scripta Mater. 42 (2000) 421-425

The samples with a 30×7×1 mm3 gauge had an average grain size about 4–6 μm in as-rolled conditions and twice as large after heat treatment.
The samples with 0.04wt%, 0.15wt%, and 0.35 wt% of Zr had the average grain size of 550 μm, 360 μm, and 170 μm, respectively.
Introducing the partition functions , where q is a real number, the self-similarity of the signal was tested.
It can also be seen that β is lower for as-rolled samples, i.e., the probability of bigger events is higher in the samples with lesser grain size, in agreement with the conjecture [11] that the grain boundaries may promote powerful avalanches due to triggering new dislocation sources in the neighboring grains.
The main conclusions following from this figure are as follows: (1) β is much lower for MgZr and varies in a range close to the values reported previously for single crystals of hexagonal metals [13]; (2) despite this difference, the effect of the grain size and strain is the same, i.e., β increases in the course of deformation, and the material with a smaller grain size shows a trend to an enhanced probability of large avalanches.

In the last few decades a great number of experiments and comprehensive studies explored the role of Sb in cast iron [5,6,7].
Sb has 17% larger atomic radius than that of Fe, therefore its addition to iron enhances the hardness, improves the wear resistance, impedes grain growth and oxidation.
The segregation of Sb decreases the grain boundary free energy.
According to the EBDS images (not shown here), the average grain size of the crust (~10 µm) was much finer than that of the bulk (~20 µm).
Most dislocations were situated at the ferrite/cementite phase boundaries extending into the ferrite grains.

Because of they have more number of interfaces between Si and Au.
The grain boundary and amorphous volume fractions were estimated by the same methods.
The annealing temperature dependence of crystal, grain boundary and amorphous volume fractions, calculated from Raman spectrum.
In addition, three data points were overlap plotted at the T=673 K in Fig. 5(a) for each crystal, grain boundary and amorphous.
Matsumura, Characterization of Novel Polycrystalline Silicon Thin-Film Transistors with Long and Narrow Grains, Jpn.