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- db: the diameter of the balls (Ø0,01 m) - ρb: the density of the balls (7800 kg/m3 ) - Nb: the number of the balls (25) - rp: the distance between the rotational axes (0,125 m) - Dv: the diameter of the vial (0,065 m) - hv: the height of the vial (0,035 m) - mp: the powder weight (0,02 kg) - Wv: the rotational speed of the vial (-13,33 s-1 ) - Wp: the rotational speed of the supporting disk (6,66 s-1 ) Fig. 1.
(a) HRTEM image of an M-ferrite grain along [010], (b) Fast-Fourier transform calculated from (a), (c) background filtered image The small nanocrystallites transform at a lower temperature to W-type hexaferrite than the bigger ones.
The fracture of the sintered HEBM material is showing plate shaped hexagonal grains (SEM) with average thickness of 200-300 nm

The difference in grain size observed between outer and intermediate zones must be due the solidification rate in centrifugal casting: the liquid metal comes into contact with the cold mould walls and as a result solid nuclei form, creating a chilled region.
This could be due to the increase in the apparent viscosity of the semisolid slurry caused by the larger number of particles (self-induced viscous drag) [16], which limits the slurry's ability to discharge trapped gases.
Conclusions The results in this work show that the centrifugal casting conditions induced variations of grain size between the outer and inner peripheries of Al / SiO2-Al2O3 5 and 10 vol% SFGMMC.

Table 1 Ratio of raw materials and sintering schedule of the samples Number Molar ratio of Al/B2O3/C Temperature (°C) A1 8:2:13 1750 A2 8:2:13 1800 A3 8:2:13 1850 A4 8:2:13 1900 A5 8:2:13 1950 B1 8:2.5:13 1800 B2 8:3:13 1800 B3 8:3.5:13 1800 Phase identification of each product was examined by powder X-ray diffractometer (X’Pert Pro MPD) with a monochromatic Cu Kα (λ=1.5406 Å) radiation source.
The different morphology Al8B4C7 grains were synthesized.
At 1800 °C, Al8B4C7 grains were hexagon plate-like with thickness of 5-10 μm and size of about 100 μm.

In this study was calculated using the total number of particles with equivalent size diameter
This thermal stress causes micro fracturing along the mineral grain boundaries, as the result, a sample of iron ore becomes more favorable for grinding.
Numerical simulations of heating samples containing pyrite demonstrated that rapid heating occurs with contact of microwave in a transparent matrix and showed that the sample was fractured due to temperature gradients across grain boundaries.

This kind of foil is characterized by columnar, brittle grain structure which can be improved by final annealing process.
As a result, even if nickel wire made by melt metallurgy meets the standards, a number of trace elements and their actual content may largely differ from melt to melt.
Initially, grain structures of welding zone, heat affected zone and parent material differ from each other.

In comparison, the microstructure evolution during stage 1 has received much less attention though its impact is critical for achieving successful stage 2 forming via control of grain size and crystallographic texture.
It should also be noted that the final deformed grain sizes and the misorientation distributions obtained from EBSD were approximately the same for all 0 20 40 60 80 100 120 140 160 180 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Equivalent Strain Equivalent Stress (MPa) Figure. 1.
It should also be noted that the absolute number of particles also increased with delay time.

Fig.1: Ishikawa diagram summarizing factors affecting the LFC quality Fig. 2: Pattern dimensions in 3-D In this experiment silica sands with the grain sizes of #16-30, #40-60 and #60-100 were used for mould making.
Table1: Levels of the independent variables Independent Variables Symbol Levels -1 0 1 Pouring temperature A (°C) 700 720 740 Slurry viscosity B (Sec) 20 28 36 Vibration time C (Sec) 30 60 90 Sand grain size D (AFS) 30 60 90 Results and discussion The thinnest section was selected due to the reason that this section is the most difficult part to be filled.
It should be noted that based on the selected variables, the number of experiments was 16 (24) plus another four more trials which were considered as the centre points for each variables.

Furthermore, TiC is also an effective grain refiner since it acts as the nucleus of α- Al during the refinement of aluminum alloys [2].
In addition to its appeal from a basic science standpoint, the final motivation for the study is to explore the grain refinement mechanism of Al-Ti-C master alloys in the future.
Since the Ti-terminated and the C-terminated slabs contain the different number of Ti and C atoms, the following calculation are divided into two groups.

In order to identify modulus of viscosity were carried out 3 experiments for sample weight with the grain size composition from 80 to 100 microns.
Grain size composition was calculated by the equivalent size of particles in equation: , (4) where di is logarithmic mean of i faction size; xi is content ratio of i faction in mixture.
Sample number Humidity, [%] Normal stress in layer, [g/mm2] Shear stress in layer, [g/mm2] Modulus of viscosity Equivalent size of particles, [mm/um] 1 2 3 4 5 6 1 0 0.044 0.018 0.41 86/0.086 10 0.049 0.027 0.55 20 0.053 0.029 0.56 30 0.058 0.025 0.43 40 0.062 0.030 0.001 50 0.071 0.051 0.001 2 1 0.046 0.019 0.43 84/0.0084 10 0.050 0.028 0.56 20 0.055 0.030 0.55 30 0.060 0.027 0.05 40 0.064 0.029 0.001 50 0.069 0.039 0.001 3 0 0.044 0.017 0.55 87/0.087 10 0.048 0.026 0.82 20 0.053 0.028 0.95 30 0.057 0.024 0.06 40 0.062 0.031 0.001 50 0.066 0.049 0.001 Modulus of viscosity for ash microspheres was identified from 0 to 50% of humidity.

Industrial pure titanium plates are excellent in performance and easy to weld and braze, so they are used in a large number of aircraft and engine parts [1,2].
Fig. 6 Microstructure of different section of titanium sheets (a)GR1, (b)GR2, (c)TA1-1, (d)TA1-2 Compared with the cross-section micro-morphology of GR1, GR2 and TA1, the grain size of TA1 is smaller and the twin crystal is relatively more.
In GR1 and GR2, only a small amount of twins exist, and the crystal grains are large, which greatly improves the plasticity of the material.