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Mechanical properties of DP steels depend on a number of parameters including the strength, morphology and volume fraction of the constituent phases [3-8].
The strength of ferrite is controlled by the steel chemistry and its grain size [9] while the martensite properties depend on its carbon concentration [3,4,9,10] and its scale [11].
The martensite grain structure in low heating rate steels forms an almost complete fine scale network lying on ferrite grain boundaries whereas the martensite islands in DP steels produced at high heating rate (100 ºC/sec) are larger and mostly banded.

These intermetallics were not limited to the bond interface, but formed along the grain boundaries and were observed to a distance of 80 µm inside the magnesium alloy.
The trace shows a number of peaks that correspond to the microstructural developments that were observed at the joint region (see Fig. 1 and 3).
This result is consistent with metallographic observations which did not show any change in grain size at regions adjacent to the bonded interface.
In contrast, the intermetallics were dispersed throughout the joint for the AZ31/Ni/316L bonds and were observed at grain boundaries within the magnesium alloy.

It is apparent in the literature that there has been very limited number of study that deal with the quantitative analysis involving the use of empirical formulas in describing the relationship between the capacitance and surface area of electrode, particularly the SSA determined from the X-ray diffraction data [20, 21, 22].
The EFB fibers were first carbonized at low temperature to produce pre-carbonized EFB fibers, followed by grinding, milling and sieving to produce self-adhesive carbon grains (SACG) [27].
Young ’ s modulus of carbon from self-adhesive carbon grain of oil palm bunches.
Electrical and mechanical properties of carbon pellets from acid (HNO3) treated self-adhesive carbon grain from oil palm empty fruit bunch.

Films with amorphous structure have σd ~ 10-10-10-9 Ω -1cm-1 while those with a measured crystalline fraction have σd ~ 10-7-10-5 Ω -1cm-1, depending on the amount of crystalline fraction and grain size.
This constraint severely reduces the number of candidate materials for substrate, with most common choices typically falling on glass or stainless steel.
The average grain size calculated from XRD spectra (not shown) of nanocrystalline samples was ~30 nm.
Films with amorphous structure have σd ~ 10-10 -10-9 Ω -1cm-1 while those with crystalline fraction detected by Raman have σd ~ 10-7-10-5 Ω -1cm-1, depending on their crystalline fraction and grain size.

The reason of the XRD peaks broadening is attributed to the refinement of grain size.
Fig. 5a shows the SEM image of Ni0 after phase transformation, as can be seen from Fig.5a the grain size of products are homogeneous and is about 70-80 nanometers with no obvious aggregation observed.
After a certain activation time as milling reduces the particle size, it would thoroughly mix the components and increases the number of chemically active defect.
The grain size of products are homogeneous and is about 70-80 nanometers and no obvious aggregation is observed.

The brighter particles are related to phases having elements with high atomic number.
Apart from a few large bright particles, smaller particles are present in the bulk as well as decorating the grain boundaries.
For a slower cooling rate, such as 1 K/min, there are more particles present in the matrix as well as along the grain boundaries (Fig. 3(a)).
It is well known that during the cooling of an Al-Zn-Mg alloy after solution heat treatment, precipitation of η-MgZn2 phase mainly occurs via heterogeneous nucleation on dispersoids and grain boundaries [7].

Whereas, the interface of nano-powder appears a large number of soft and hard aggregations in the atmospheric environment due to volume effect, surface effect, quantum size effect and so on in the nanoparticles, this leads to poor performance of the nano-powers.
It is clear that the dispersant dosages on the crystallinity have not influence, the diffraction peaks with high intensity show the high crystallinity of the powders, which can be attributed to the use of dispersant OP-10 that it only adsorb on solid surface and reduce the surface tension, restrains the grain grow up.
Grain size effects on dielectric properties of barium strontium titanate composite ceramics[J].Materials Research Bulletin, 2013,48(3):973-977
Hydrothermal synthesis ofBaTiO3 from different Ti-precursors and microstructural and electrical properties of sintered samples with submicrometric grain size[J].

A number of different composite materials have been fabricated into nozzle inserts, thrust chamber throats, etc.
The Nextel 720 fiber has both a secondary phase and elongated grains incorporated into its microstructure.
The mullite (55 vol%) is present primarily as needles surrounding the Al2O3 grains (45 vol%).
However, the recent work of Göring and Schneider [3], illustrated that at temperature of 1300o C and above grain growth of Nextel 720 resulted in the decrease of the strength in heat treatment times of 2h.

Grain size of powdery fraction was lower than 200 µm and was determined by the sieve analysis (Fig.6).
The cumulative wear in g/cm2 for a number of test cycles.
Each cycle represents a 500 m of path of friction (description in the Table No.1 above, circle – pure oil, square oil+coal, triangle oil+ore) Discussion In the case of presence a fraction with particle size of less than 200 μm for both material combination and corrosion state, the increasing intensity of wear was observed, which partially can be explained by the role the fine – grain particles as abrasive factor.
Generally at higher altitudes and farther away from the source will be observed increase in the share of the smallest grain fraction.

Thin layers of the powder (common grain size ranges from 25 to 200 m, depending on the material) deposited by the machine rake system are additionally pre-heated before melting.
This pre-heating helps to keep the elevated process temperature, to de-gas the powder grain surface and evaporate any adsorbed moisture, and to prevent the charged powder forming ‘clouds’ in the chamber.
Though significant number of different EBW and laser-based AM machines exists up to date, certain comparisons of critical parameters can be done.
It is mainly attributed to the fact that processing in EBM® is performed in deep vacuum, and majority of residual porosity there is attributed to the bubbles initially trapped in the powder grain.