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The complex formalisms are functions to show the grain, grain boundary and interface properties of ceramics, which included the determination of capacitance of grain (Cb) with grain boundary (Cgb), electrical conductivity, and relaxation frequency [10].
The crystal structure for all of BT phase detected is tetragonal with lattice parameter of ‘c’ is longer than ‘a’ which is 4.038 and 3.994 respectively with PDF number of 05-626.
On the other hand, a secondary phase formed in sample S1 and S2 where barium orthotitanate (Ba2Tio4) was detected at 2θ = 29.24° with PDF number of 35-813.
The grain structure arrangement from S3 was seen closely packed compared to other samples.
Acknowledgements The authors would like to acknowledge the financial support provided by the Malaysian government which is from Fundamental Research Grant Scheme, FRGS (grant number: 9003-00280).

Firstly, the cBN grains of the wheel surface were truncated by TTMD.
However, the number of spark-out grinding was increased with increasing work speed.
Therefore, it is considered that the surface roughness slightly decreased due to the increase in the number of truncated grains which act like burnishing process.
In RRMG, the burnishing effect was enhanced because the tip of abrasive grains was flattened by TTMD and the cutting depth of grains became very small at high work speed.
(1) The surface roughness of the workpiece decreases with increasing work speed of RRMG because the cutting depth of grains is very small, and the number of grains providing a burnishing effect increases

At identical porosity, concentration of nano-voids in the vicinity of grain boundaries causes the decrease in the shear strength of nanostructured and ultrafine-grained ceramics.
The RVE dimensions were estimated such that it contains a lower possible number of interacted structural elements of a lower-scale level providing equal values of statistically averaged physical-mechanical property parameters.
Continuum mechanics approach is appropriate for describing the deformation and damage processes on mesoscale level, if the size of structural elements lm (grain size of matrix, grain size of reinforced particles) is greater than 50 nm.
Mechanical state of grains of matrix, strengthening particles, grain boundaries phase is described by meso-scale mechanical parameters.
This effect is negligible for nanocomposites because of fine grain size.

Development of hybrid welding is ongoing with novel fillers to refine weld metal grain structure and improve weld properties.
Initial trials were performed to select a reduced number of processes from the large number of possible options, in terms of choice of laser source and spot size, and choice between autogenous laser welding and hybrid laser-MIG welding.
Welds contained a number of irregularly shaped cavities, in addition to spherical gas porosity.
Number in brackets indicates number of tensile tests from which mean values were calculated.
As an example of an initial result of work in progress, Fig. 7 shows the grain structure achieved in the weld metal with one such filler composition, containing a grain refiner addition, compared to a filler of conventional composition.

Procedure for quantitative evaluation of the α(Mg) area of the grain flat section.
While studying the literature on the subject, one can find out that the structure of the QE22 alloy in the post-casting state consists of grains and areas adjacent to the grain borders [3,4,8] (Fig. 3).
Inside of the fusion weld one can see repeated fragmentations of a(Mg) grains (average surface area of 327 µm2).
The rate of change that amounts to 195% may suggest a significant differentiation of the grain size.
The assumed working hypothesis was that a(Mg) solution grains came from the same population.

Neither too high nor too low stirring speed is a benefit to form the semi-solid state; stirring time is also not too long; higher casting temperature is unfavorable; with the increasing of standing time, the steady-state apparent viscosity of the slurry increases rapidly, the number of nucleation increases and the crystalline structure becomes finer. 1 Introduction As the lightest structural materials, Magnesium alloys offer various possibilities in regards to applications in the automotive and aeronautical industries because of a number of desirable features, including low density, high specific strength and rigidity, high electric and thermal conduction, etc.
It can be seen that with the increasing of stirring speed the pre-crystal solid grains in the semi-solid structure become uniform, fine and closely globular crystal gradually.
When the stirring speed is 10rpm, it is typical dendritic crystal morphology, the pre-crystal solid grains are coarse and its boundary is rough.
However, when the stirring speed is beyond 1200rpm, the crystal density will decrease because the heat quantity produced by the stirring process will remelt the pre-crystalline grains.
With the increasing of the standing time, the aggregation occurs between the solid grains and then coarsens, and the steady-state viscosity increases significantly.

These alloy elements are mainly distributed in the form of reticular and granular structure along the grain boundaries.
Fe atoms have a clear trend of distribution along the grain boundaries, while a majority of other atoms, such as Zn, Sn, In and Ga, are evenly distributed and minority assemble along the grain boundaries.
Superfluous Bi atoms are distributed along the grain boundaries, especially the junctions of adjacent grain boundaries, where Bi and other elements form new phases and these phases are distributed as dotting or granular microstructure in the matrix.
Conclusions 1) Fe atoms are mainly distributed along grain boundaries, and form intermetallic compounds with Al, Sn and other elements in Al-Bi-Sn-In-Ga alloy.
These new phases, presenting partial enrichment, gather in the junctions of grain boundaries.

Silca and its composite powders added different amount of microsilica were ground in a planetary ball mill (QM-3SP4) at various grinding period with addition of a certain number of grinding aid.
The surface of the particle happened to amorphization, and occurred grain refinement and lattice distortion.
Experiment Silica and microsilica powder were used as raw materials, grinded in planetary ball mill (QM-3SP4) with addition of a certain number of grinding aid.
Changes of Grain siza and lattice distortion.
Powder is composed with several thin crystalline grains, which connect through crystal boundary.

In this research work the effects of impact force, such as increasing in the surface temperature of powders, the number of vacancies and pipe diffusion, on the strain and grain size of final powders have been studied.
This research work represents the optimum parameters to diffuse Fe in Cu and also the effects of impact force on the strain and grain size of final powders in Fe-Cu system have been studied.
Using TAGUCHI helps to design samples to find these optimums and reduces the number of required samples and consequent tests.
Impact energy of balls has a direct relationship with their speed and their numbers (which create the PBR factor).

Transverse rupture strength is mainly affected by grain size, as the grain size increases; the values of transverse rupture strength and wear resistance increases and decreases respectively [7].
Fig.2 Variation of fracture toughness with binder %age and grain size [6].
Significant number of research studies has been carried out and reported to machine this material with conventional machining processes.
Gadalla and Tsai [38] studied the formation of cavities by dislodging of the WC grain.
The chances of occurrence of the micro-cracks were more in WC-12%Co (0.93 grain size) as compared to WC-12%Co (0.85 grain size).