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Natural graphite was used as the primary filler (30-70 wt%) with relatively large average grain size (20-80 µm, Carbosint, Hungary) because according to the literature thus the electrical conductivity can be increased to the largest degree with the least possible rise of viscosity.
As an auxiliary filler (1-9 wt%) carbon nanotubes were used, which have the capability for increasing the mechanical strength of the material, and forming electrical contacts between the larger grains of graphite.
CB has smaller grains than graphite, therefore it can fill the voids among the larger graphite particles in the percolation network, which results in an elevated number of electrical contacts and hence better conductivity.
Thereafter the prepared composite pieces were grinded and sieved through a 3 mm sieve to achieve sufficient grain size.
SEM images of the filler mixture after dispersion (A: graphite whisker, B: nanotube connected to the graphite grain, C: destroyed nanotubes on the graphite surface after 6 hours of ultrasonic treatment) Conclusion Despite our expectations the addition of nanotubes did not increases the conductivity significantly, apparently because nanotubes are too short to bridge the void between graphite particles (Figure 4/B), and rather stick to the surface of the grains.

For milling tools as the tool diameter decreases, too much number of teeth leads to the space between the cutting teeth and the cutting point decreases, which in turn make chip breaking more difficulty.
The most widely used tool materials include crystal diamond, fine grain and ultra-fine grain cemented carbide.
The fine grain and ultra-fine grain carbide cutting tools refer to the grain size in the range of 0.2-1.3µm.
With the refinement of the carbide grains, the hard phase size decreases, the binder phase distribution is more uniform, material hardness and bending strength is increased, and in hence expands the carbide applications.

Heavy deformation and more particularly milling result in fragmentation, nanocrystallisation (grain refinement) and generation of fresh surt·aces and grain boundaries that accelerate such oxidation processes.
However, the oxide obtained in this manner undergoes rapid heating sometimes up to its melting temperature due to quasi-adiabatic combustion conditions and the resulting powder has coarse grains.
Toe process is of only academic interest as it takes preciously reduced Zr metal back to its natural coarse grain oxide state.
We have shown [7] that if instead of an 02 atmosphere in the mill, a partial pressure of Oz in argon gas is introduced that just corresponds to the number of oxygen atoms needed to oxidise the metal in the mill, a gradual oxidation occurs that yields a nanograined oxide powder.
On the other hand, even after very long milling times, a mixture of preformed crystalline ZrO2 and Cu powder under inert gas does not lead to any detectable amounts of amorphous ZrO2 oxide although it does lead to grain refinement [7].

Moreover, the Joule heating accelerates the melting off of dendrites, which primarily lead to the grain multiplication.
It has been amply demonstrated that grain multiplication is an important and general source of equiaxed crystals in castings and ingots [7].
As mentioned above, the intense forced convection induced by electromagnetic forces generally promotes both the decrease of superheat and the homogenization of the melt temperature. the crystallization proceeds simultaneously throughout the undercooled melt around a number of suspended nuclei which is the dendrite arms broken by electromagnetic stirring, and this increasing nucleation generally results in the appearance of a fine-grained equiaxed structure and a higher degree of homogeneity in crystallization.
Hot working can break down the cast structure and achieve uniformity of grain size as well as constituent size and distribution.
As shown in Fig.5, the billet cast under the electromagnetic field shows much finer grain size and more uniform structure.

So Ti can rise in steel refining grain, and the effect of precipitation hardening.
The addition of Re elements also can refine grain, change the state of inclusions in the steel to reduce the harmful amount of inclusions, reduce corrosion source point, so as to improve the atmospheric corrosion resistance of steel. 3.
Due to the lower heating and keeping temperature in thermal phase zone, diffusion is relatively slow, diffusion processes is boundary diffusion-based, so the higher growth velocity along the austenite grain boundary ferrite, which grew to ferrite low speed, resulting in the formation of irregular, the long axis of the ferrite austenite grain boundaries parallel to the island, thus making the transition from its martensitic state also showed this distribution. 3.3 Mechanics property and formability of weathering steel Because of weathering steel in addition to need to have good corrosion resistance, but still need to have a sufficiently high strength, ductility and toughness and the best strength and toughness .
The Plastic strain ratio through the determination of tensile test is also the important indicator to measure Steel form ability, which means that under the same stress, conditions the different vertical deformation between Thickness direction and Plate plane direction. 4 Conclusion and prospect At present in domestic，a large number of weathering steels are applied to vehicles, container industry.
Refine grain boundary was beneficial to the improvement of the material strength and plasticity.

The OAD method is a sophisticated physical evaporation technique for thin film deposition but because of the self-shadowing effect and the formation of columnar grains, the novel properties can depend on the formation of these columnar grains [9].
Three main zones of thin film growth are defined by Ts/Tm: the first zone (Z1, Ts/Tm <0.3) corresponds to the films consisting of fiber crystals with voided boundaries, the second zone (Z2, 0.3grains having very distinct boundaries, and the last zone (Z3, Ts/Tm >0.5) corresponds to a structure with equiaxed grains.
The value of surface roughness on a larger scale (tens of nm) arises from the large grains and hillocks formed at high deposition rates.
At lower deposition rates the roughness is determined by the size of the columnar grains and the depths of the voids between them.
At higher deposition rates the significant increase in roughness is apparently related to the greater number of large hillocks protruding out from the film surface.

Austenitic steels are more prone to plastic deformation due to the large number of slip systems.
Autors indicates that for steel ELC X04Cr14Ni12TiN, resizing a layer of plastic deformation is related mainly to the material structure and properties of austenitic grain size.
Fig.2 Plastic deformation of the surface, local plastic deformation in austenitic grain-hardening surface, zone of hole H and D Fig.3 Plastic deformation of the surface to a local plastic deformation in the austenitic grain, zone of hole B To plastic deformation occurs under the surface finish and the local austenite grains.
At the same time claim autor confirmed that this is true for smaller austenite grains (~to 60 mm).
Have identified areas consist of a continuous plastically deformed microstructure and the depth below the machined surface, which was localized plastic deformation in the austenite grains isolated.

Techniques include, heuristic coarse-grain to fine-grain triangulation, some formulate this as estimation problem and apply different optimization techniques, [7].
Unlike previous works, our work is based on simplified model that can be simple to implement and be adjusted to different resolution depending on the needs of course-grain or fine-grain accuracy.
There are infinite numbers of answers for this equation.
Unlike previous works, our work is based simplified model that can be simple to implement and be adjusted to different resolution depending on the needs of course-grain or fine-grain.

The earth usable for the unburned clay constructions consists of three basic components: sand (grain size 0.06 - 2 mm), dust particles (grain size 0.002 – 0.06 mm) and clay (grain size up to 0.002 mm).
We used fraction of sand with grain size up to 1 mm (40%) and a fraction of grain size up to 2 mm (60%).
Fig. 2 Clay test body Table 1 Composition of the clay mixtures Set Clay Sand/clay ratio Water/clay ratio Number of test bodies SI Illite, kaolinite 75/25 0.37 6 SII Illite, kaolinite 80/20 0.37 6 SIII Illite, kaolinite 85/15 0.37 6 SIV Illite, kaolinite 75/25 0.295 6 SV Illite, kaolinite 75/25 0.335 6 Test bodies were created by ramming into the steel molds of given dimensions.
This is probably due to inaccuracy of measurement, since the body sets SIII showed a high degree of friability, and it was difficult to maintain the surface of the sample without presence of grains of sand.

Fig 3 The relationship between L bond content and wheel’s facture strength What can be seen from figure 3 was: when L bond takes 20wt%, the fracture strength of wheel reached its top and the bond retention to diamond grains maximized.
In the author’s point of view, when PDC was processed under the same condition, high concentration wheels had more diamond grains participating in the grinding process thus less force was exerted to each individual grain, if the retention were strong enough, the diamond grains could stay even longer and work longer.
The numbers clearly shows, vitrified bond has a stronger binding force than resin bond, so does the retention to diamond, this gives it benefit both in lifespan and efficiency.
It is believed the culprit is the 830℃ sintering temperature, together with the open air sintering environment, this may dent the diamond grain inside.
L’s sintering temperature is 720℃ and A’s is 760℃, both are under the threshold 800℃, above which it is believed to do serious hard to the diamond grain embedded.