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The EB-polished surfaces are evaluated with varying the energy density Ed (2-12J/cm2) and the number of pulse � (10-90shot).
At the surface before EB-polishing, large crystal grains can be clearly observed.
For EB-polished surfaces, the crystal grains are small and less distinct.
Conclusions (1) Thin resolidified layer is formed on stainless steels surface by EB-polishing, and the crystal grain size becomes small and Cr oxide is uniformly rearranged in the layer

Properties of the RCS * Grain Fineness Number (GFN) is a measure of average size of grains in sand.
American Foundry Society (AFS) GFN is measuring the grain fineness of a sand system

The number of graphene layers is not more than 30, the diameter is from 10 to 60 nanometers.
The average grain size is ~ 10–15 microns.
Image of the surfaces of the samples of the series of experiments No 1 and No 2, obtained on a scanning electron microscope NEON 40 It should be noted that the grain boundaries in the samples of experiment series No 1 are more clearly defined than in the samples of experiment series No 2, which is confirmed by the data of atomic force microscopy.
Most of the hydrogen is adsorbed by chromium and is located at the grain boundaries and in microcracks, and some of the hydrogen is embedded in the crystal lattice.

Unlike the conventional die casting process, in which superheated liquid alloy is the starting materials, the semi-solid forming process uses semi-solid slurry as a starting materials for component forming, so the semi-solid forming process provides a number of advantages over other magnesium alloys casting technologies, such as less porosity, complex shapes, reduced macro-segregation and hot tearing[1].
Due to the grains in the 10℃/s 3℃/s Time /min Temperature /℃ Fig.2 Schematic view of heating technology Specimen Jig Jig Graphite slice Thermocouple Press Press Fig.1 Schematic view of semi-solid compression Fig.3 Stress-strain curves for the AZ91D alloy at various deformation temperatures 0 5 10 15 20 25 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 450℃ 500℃ 530℃ 550℃ Strain Stress/MPa 0.025 Dendritic structure Nondendritic structure 570℃ microstructure of the AZ91D alloy with dendritic structure were connected to the network framework(Fig.4a), and the stress enduring capability of the structure with the network framework characteristic was high, It was found in Fig.3 that the solid compression stress of the AZ91D alloy with dendritic structure was bigger than the solid and semi-solid compression stress of the AZ91D alloy with non-dendritic structure.
But after the semi-solid isothermal treatment of the AZ91D alloy was carried out for over 60 min at 570℃ and followed by water quenching, the primary grain morphology in the structure of the AZ91D alloy gradually changed to sphere shape (Fig.4b), due to the deformation mechanism of these sphere grains were mainly the rotation, slip and movement during the semi-solid compressive deformation(Fig.5)[4,5], and with the deformation temperature increasing, the liquid proportion in the structure of the alloys increased, so it was also found in Fig.3 that the semi-solid compression stress of the AZ91D alloy with non-dendritic structure were all lower than the solid compression stress, and with the deformation temperature increasing, the compressive stress decreased.

Both alloys at extrusion condition show grain size of about 4-8 µm.
In the case of alloy2, as shown in Fig.1 (b), a high density fiber-like structure was seen along the extrusion direction for the large amount of grain boundary phase.
It showed clearly that many fine particles distributed along the grain boundary and in the matrix.
This Laves phase with MgCu2 type has cubic topological and close-packed structure, thus it is very difficult for dislocation to nucleate and slip due to high coordination number and space availability in Laves phase [6], which make Laves phase own outstanding thermal stability and higher strength at elevated temperature.

The ball-milled slurry was filtered by using filter cloth whose mesh number is 100, cast onto the glass substrate, and dried at 60℃.
It is found that the average grain size increases with increasing sintering temperature.
The grain of sample sintered at 1250℃ is larger and there are less voids.
So with the sintering temperature increasing, the grain size increases and the porosity decreases.

Furthermore mechanical and metallurgical properties like Tensile test is made through universal testing machine, Micro-hardness through Vickers hardness tester and Micro structure through Optical Microscopy is done for investigation. 1 Introduction In the bygone era aluminium and its alloys composites are the most likely material for weight reduction, but in this contemporary engineering world Magnesium Metal Matrix Composites (MMMC) which has density about 30% lower than aluminium alloy gains the attraction towards application fields because of its keen physical characteristics and cast ability. [1] The significant demand on materials for overall performance has led to ample research in these composite materials. [2, 3] The casting process particularly stir casting method have been advise method as they impart themselves to produce large number of complex shaped components. [4] This work depicts the usage of tungsten carbide in AZ31B for synthesizing magnesium composite by stir casting
It is evident that increased percentage of boron carbide reinforcements exhibited superior hardness of about 97.06 HV which is due to [6] refined grain size, enhanced surface area of AZ91, [5] dispersion and increased hardness of Reinforced ceramics.
From Figure 8 (b), it is evident that there is a reduction in grain size with diffusion of boron carbide particles in its hard phase.
· Dispersion of B4C is also evident with reduced grain size in microstructure characterization

The grain size of ZAO thin films increase and the crystalline quality improves because high substrate temperature can provide sufficient energy in the crystallization process.
Based on the XRD results, the average crystallite sizes were estimated by Scherrer formula as follows[8]: D=0.9λ/βcosθ (1) Where D is the grain size, λ is the X-ray wavelength, θ is the Bragg angle, and β is the full width at half maximum(FWHM) of ZAO (002) diffraction peak.
Therefore, it was necessary to try to decrease the numbers of scattering centers to improve the carrier mobility of the ZAO films.
But this change is not infinite, because the grain size is not infinitely large.

Also the grain size of the prepared magnetic powder is small with an average of 8 nm.
Under coarse conditions, the average grain size is only about 20 nm.
The average grain size of the magnetic powder prepared by the sedimentation oxidation is about 50 nm, it can reach about 200 nm under coarse conditions.
The absorbency results that were measured were as follows: （A0=0.865） A1=0.866 A2=0.804 A3=0.792 A4=0.767 A5=0.761 A6=0.756 A7=0.752 Use the ordinal number of sampling in the catalyzing experiment as the horizontal axis, use the absorbency of the water sampling as the vertical axis, we drew its absorbency curve which was in Fig. 3.

Such form of X-ray diffraction pattern confirms the composite type of those layers as a result of titanium crystalline grains embedding to the amorphous Ni-P matrix. 10 20 30 40 50 60 70 80 90 Ni-P Ti Ti Ti Ti 2���� Fig.1 X-ray diffraction pattern of Ni-P+Ti composite layers.
The presence of Ti in the Ni-P matrix changes the heterogeneity of the surface and increases the number of interfaces between Ni and incorporated particles.
All obtained layers are of mat, rough metallic surface with a visible Ti embedded grains.
It proves the uniform distribution of Ti grains in the layer.