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At thick section, grain size of HPDC is smaller than grain size of squeeze casting which shown in Fig. 14.
HPDC part has ASTM grain size number 8.08.
In otherwise squeeze casting part has ASTM grain size number 7.45.
HPDC part has ASTM grain size number 8.53.
Squeeze casting part has ASTM grain size number 8.45.

The dense alumina body is sintered while maintaining the fine grains, and with the micro pores remaining in the grain boundary.
On the other hand, the crystal grains hardly developed and the main fracture type was the intergranular fracture at a sintering temperature of 1473 K, as shown in Fig. 2 (b).　
In these cases also, the crystal grains developed and the main fracture type changed from an intergranular fracture to a transcrystalline fracture when the sintering temperature increased.
There were many small pores at a low sintering temperature, and the number of pores decreased and the size of the pores developed at high sintering temperatures compared with low sintering temperatures.
Since an ultra-fine alumina powder of high purity in which densifying is possible at a low sintering temperature is used in this study, the alumina body is densified as fine crystal grains with almost no grain growth.

Researchers found that the grain structure at FZ is coarse and oriented grains, while the HAZ has finer grains, and the base metal has soft larger round grains [8, 9, 15].
While the grains at HAZ recrystallize and new grains start to form.
The numbering of the samples corresponds to that in Table 4.
Figure 6 (b) shows fine round ferrite (α) grains with light contrast, while the dark grains are perlite (P).
HAZ has two regions refined grains and coarse grains.

Modeling Under microscopic observation common metallic materials tends to show a significant distribution of grains and grain boundaries.
The shape of grain is irregular and the scale of strain is not uniform.
In this model each small part can be seen approximately as an independent grain correspond to the real grain in common metallic materials.
The simulation model is shown below, some parameters of the material part are set as follows: Table 1 Settings of scale parameters for materials in simulation Parameters Values Sample size 1mm * 1mm Number of grains 400 Average grain scale 50um Figure 5 A schematic diagram of the finite element simulation modeling Take the titanium alloy TC4 material as an example, to set the parameters of the mechanical properties of the material in the material module of Abaqus as follows: Table 2 The relevant material properties in preprocessing Paramaters Values Density 4.5g/cm^3 Young's modulus 110GPa Poisson's ratio 0.34 Yield limit 860MPa Tensile strength 967MPa After the definition of materials, modeling, loading, meshing and other pre-processing step, the peak load of 900MPa is set.
As is seen from the graph that each grain has a different stress state.

It is well known that a grating with larger number of slits gives narrower principal maxima.
It is clear by decreasing particle size that the number of atoms residing on the surface is increased.
The specific surface area (Table 2) of the particle increases as the grain size decreases.
The surface free energy calculated assuming the grains to be spheres with a surface energy of 1000 erg/cm2 [35], increases with decreasing grain size.
Because of the higher band gap, the number of electrons reaching the conduction band is relatively low, consequently, number of holes in the valance band decreases.

Spectral analysis was performed to identify the nature of changes of grains in different processes.
Relative porosity and the chemical composition have been examined, growth patterns of grain has been observed.
The number of layers depends on the rapid stabilization of the process.
This becomes clear once by the end of many grains at the same height and in the right picture by the darker grey tones.
The shape is comparable to that of sample 7. but the number of pores is much smaller.

However, it has proved difficult to prepare large defect-free crystals of Terfenol-D and the presence of a large number of defects degrades the magnentostrictive properties due to the pinning mechanism between defects and domain walls [5-7].
Under single overheating around 50℃, there are <110> <113> <214> and <125> oriented grains, as shown in Fig2a, because the temperature gradient was kept about 500 K/cm, the diffraction intensity of <110> and <113> are high, and <110> <113> oriented grains be in the majority.
The diffraction intensity of <110> and <113> are high and <110> <113> oriented grains are in the majority.
Nevertheless, there are still <111> oriented grains.
However, under the condition of multi-overheating, <111> oriented grains can be gained as shown in Fig2c and Fig2d.

Results clearly demonstrated that appropriate calcination temperature of 3mol%molYF3-CaF2 composite was below 500°C, and when the YF3-CaF2 ceramic sintering temperature was 900°C, the YF3 was uniform doped in CaF2 ceramic successfully and the grain growth was very good.
The molecules number of per unit cell is four, the cation sublattice is face-centered cubic structure, anionic sublattice is composed of simple cubic structure.
Other materials with this structure include a number of materials used as nuclear fuel, i.e.
The thermal etching surface micrographs and the grain size of the as-sintered pellets were examined by scanning electron microscopy (SEM, TM3000, Japan).
Result shown that theYF3 was uniform doped in CaF2 ceramic at 900°C successfully and the grain growth was very good.

Rockwell Hardness number was determined by the difference in depth of penetration resulting from application of initial minor load of 0.1 KN followed by major load of 1.5 KN.
It was observed that for a field area of 832927.2 µm2, total number of counts for EBM Ti-6Al-4V sample was 10371 while for wrought sample it was 3163 and both had the median grain sizes in the range 13-15 µm as shown in Fig. 8.
Grain size vs.
Grain size vs.
Grain size vs.

Deformation of austenite under conditions inhibited recrystallization at temperatures of Ar3 number of nucleation centers of a new phase in the subsequent phase transformation and, therefore, structure refinement.
Note that because of the large number of inclusions of highly dispersed carbonitride hardening phase microhardness of ferrite is 2100¸2300 MPa.
SEM image of structure of the sample treated at T3 = 600 °C and e3Σ = 31 (a) and grain boundaries misorientation angles (b).
Lowering the deformation temperature to 700¸400 °C and the increase in the total degree of deformation leads to a gradual filling of the metal the new boundaries of fine grains and a decrease in grain size up to 100 nm.
This causes a significant hardening due to the effect of grain boundary hardening and decrease of plasticity to almost zero.