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Diamond grains in a segment play the role of cutting edge whereas the bond matrix plays the role of fixing diamond grains.
Assuming the size of the matrix sample to be 14mm × 2mm and the number of particles to be 5537, a DEM model was built and is shown in Fig.1.
Fig.4 The sample of a segment containing diamond grains DEM Model for Three-Point Bending Test.
It can be seen that crack extends along the diamond grains, indicating that the failure occurs when the bonding strength between the diamond grains and metal matrix particles is weaker than that among the metal matrix particles.
The bending strength in the simulated bending test was found to decrease with the numbers of porosity.

The I-phase (Mg3Zn6Y) has a number of exceptional characteristics including high hardness, low surface energy and excellent high-temperature plasticity [1,3].
When the acoustic power density is at a low level (3 W/mL), most of a-Mg grains are spherical while a small number of them are rosette-like with some dendritic arms still existing.
As the acoustic power density increases to 6 W/mL, a-Mg grains are converted into fine and spherical grains.
A large number of cavitation bubbles form and grow when the melt is subjected to local tensile stress.
Therefore, a large number of nuclei form around the cavitation bubbles.

However, a number of Mg12Zn(Y,Gd) phases and Mg(Gd,Y)Zn phases retains after heat-treatment result that the increase of concentration in the grains is not significant, and so the solution strengthening effect on the YS is not also obvious.
The dislocations are gathered at the grain boundaries finally, and thus it is particularly important to prevent the dislocation movement with the secondary phase at grain boundary.
Nevertheless, with the heat-treatment process, the reduction of the number of LPSO phases and effect of dissevering on the LPSO phase by Mg(Gd,Y)Zn phase result the decrease of UTS and elongation.
These phases are network distributing along the grain boundaries discontinuously
However, the reduction of the number of LPSO phases and effect of dissevering on the LPSO phase by Mg(Gd,Y)Zn phase result the decrease of UTS and elongation with the heat-treatment time prolonged.

Thus, meta-models which are extracted from the results of a limited number of FE simulation studies are more and more used to find the optimal process design parameters.
The accuracy of an RSM is highly dependent on the number of input data points.
The austenitic grain size was determined using the linear intercept method.
DRX kinetics (1) Peak strain (2) Critical strain (3) Steady-state strain (4) Dyn. recr. grain size (5) Grain growth (6) Design of experiments (DOE).
To predict GG the annealed specimens were analyzed in terms of grain sizes.

The results show that the addition of B makes part of Zr become precipitation present in grains and grain boundaries as the small plate sheet of second phase from solution.
With the B sample test results of the XRD When we made the energy spectrum analysis using Inca Energy EDS, there ware no B elements in the spectrum, because the atomic number of B is small.
The analysis of the energy spectrum shows that there are fine precipitates no matter on grain boundary or inside of the grain.
According to the analysis of the energy spectrum, the second phase particles of Zr containing are appeared both on grain boundary and in inside of grain.
And making parts of Zr precipitated in inside of the grain and on the grain boundary as the form of flaky second phase particles from solution.

The simulation of a representative microstructure starts by populating these cells with pre-specified numbers of nuclei.
(a) The structure domain divided into a number of finite elements; one element is shown with its expected array of cells.
At this stage of the 2D model formulation, these are numbers that reduce to angles of 0°, 30°, 45°and 90° with the principal straining direction.
Fig. 10 shows the grain structure in element number 3 located at the bottom-left hand corner of the specimen (third from bottom of element set A (shaded)).
Effect of grain size Fig. 12 displays the stress predictions for a change in the initial grain sizes, one with large grains and the other with small grains.

Accordingly, a slightly reduced twin volume fraction, but an increased number of smaller twins was observed after compression in the aged samples.
This has enabled a greater number of twin/particle interactions to be studied over a large area than using transmission electron microscopy.
Moreover, particles decorating the grain boundaries are present in in both aged specimens.
The average grain size values are included as insets in the OM micrographs.
The number of twins per unit area of the three samples was also calculated by counting manually the number of twins on several SEM pictures.

Further increasing Nd content leads to the coarsening of primary α-Mg grains.
As the Nd content is further increased to 1.5wt.%, grain coarsening of primary α-Mg occurs (Fig. 1(d)).
When the content of Nd reaches 4 wt.%, a large number of polylateral phases emerge in the microstructure, as shown in Fig. 1(f) (marked by white arrows).
On the other hand, the refinement of primary α-Mg grains enlarge the grain boundary areas including secondary dendrite arms boundary, which makes the residual liquid phase decrease and dispersedly distributes.
A large number of massive Al2Nd phases emerge when Nd content reaches 4.0wt

The low frequency arc was due to the grain boundary and grain effect, and the high frequency arc was attributable to the grain effect [9-10].
The grain and grain boundaries resistance with different Al doping ratio are shown in Fig. 3 (b).
The grain and grain boundary are significantly presented in surface micrographs.
The number of grain boundaries is inverse proportional to the grain size.
The resistance of grain and grain boundary are obtained approximately though impedance spectra analysis.

In addition, the equiaxial grains exist in the zirconia coating according to TEM, but the grain size is not uniform.
The reason is that part of agglomerated feeding powders have been crushed and transformed into a large number of small particles in the gas transportation process[8].
Furthermore, a small number of unmolten nanometer powders loose deposit in the coating.
The majority of the grain size is in the range of 50-120nm, with the good crystal grain and the clear crystal boundary.
B Equiaxed grain A Columnar grains Figure 5.