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Milling the samples were carried out for the specified time of 7, 15, 30, 45, 60, 90 and 180 minutes at the number of 45 rotations / min.
Average grain size is the parameter of the of the largest grain size which remain on the sieve downfall to 50% of the total amount of grains.
In this CFBC ash we can also observe the largest decrease of average grain milling - after 7 minutes, the average grain size decreased sevenfold.
For other ashes, the difference of average grain size of samples 0 and I smaller - after 7 minutes, the average grain decreased approximately twofold.
Average grain diameter (R 50%) of fly ashes.

The CIP done at room temperature was to suppress grain growth.
The TEM image shown in Fig. 1(c) indicated that MA’ed powder had about 7~8 nm grain size.
The TEM photo shown in Fig. 5(a) reveals submicrometer size, rather round (Al+12.5%Cu)3Zr grains (Fig. 5(b)).
Initially formed nano-size grains, which were generally expected to display better ductility via grain boundary sliding and diffusional creep, grew by heating.
Doychak (Ed.), TMS, Warrendale, PA (1989) 277 (004) (114) (114)(110)(114) (004) (114) (110) [110] (c) (004) (114) (114)(110)(114) (004) (114) (110) [110] (004) (114) (114)(110)(114) (004) (114) (110) [110] (c) Al Zr Cu Zr Zr Cu 62.88%Al+12.5%Cu+24.62%Zr spot ‘X’ (b) Energy, E/keV 0 15 10 5 Intensity (round grain) Al Zr Cu Zr Zr Cu 62.88%Al+12.5%Cu+24.62%Zr spot ‘X’ (b) Energy, E/keV 0 15 10 5 Intensity (round grain) Energy, E/keV Al Zr Cu Zr Zr Cu 36.55%Al+8.9%Cu+54.55%Zr spot ‘Y’ Intensity 0 15 10 5 (d) (dark, small particle) Energy, E/keV Al Zr Cu Zr Zr Cu 36.55%Al+8.9%Cu+54.55%Zr spot ‘Y’ Intensity 0 15 10 5 (d) (dark, small particle) Y (a) 100��� � X Y (a) 100��� � X Journal Title and Volume Number (to be inserted by the publisher) [10] R.

The higher wheel speed results in a decrease in the chip thickness and sectional area of the single grain on the premise of keeping material removal rates.
So the grinding force of the active grains and wheel wear are reduced, and the wheel life is improved.
Table 3 HSDG conditions with vetrified CBN wheel Serial number 1-1 1-2 1-3 1-4 vs (m/s) 60~150 150 150 150 vw (m/min) 2 1~6 6 1~4 ap (mm) 0.1 0.2 0.2~1 0.2~0.8 z'w(mm 3/mms) 3.3 3.3~20 20~100 13.3 Table 4 HSDG conditions with resin bond diamond wheel Serial number 1-1 1-2 1-3 1-4 vs (m/s) 60~150 150 150 150 vw (m/min) 2 1~6 6 1~4 ap (mm) 0.1 0.2 0.2~1.8 0.2~0.8 z'w(mm 3/mms) 3.3 3.3~20 20~180 13.3 Results and discussions Characteristics and analysis of grinding force.
But the grinding depth and force of single grain is higher under above conditions.
While, the ploughing section area of grain per unit time and width Sw can be defined as 0 max 0 cos sc w s g C v h l S C v A         (6) where C0 is the grain concentration of wheel surface, lc the contact length and θ the semi-included angle at the bottom of grinding chip.

Additionally, low scan speed promotes lower cooling rate of the melted powder, which results in larger grain size of the material.
Igarashi (1977) showed in his study that in ferrites, magnetic saturation of the material is independent of grain size and proportional to the density of the material and that coercivity is inversely proportional to grain size [10].
Annealing improves the magnetic properties of the material by relaxing the inner stresses in the material, increasing the grain size and reducing lattice defects through recrystallisation process [11].
The increase in permeability was mostly attributed to grain growth in the material, which was shown to only be present in the case of high annealing temperatures.
Periodic magnetic flux was calculated from the measured data by (Eq. 1) and the induced varying electromotive force in the secondary coil by (Eq. 2), where N1 – is number of turns of the primary coil, N2 – the number of turns of the secondary coil, I – the current in the primary coil and v the induced electromotive force.

When extruded at 920℃, the transverse macrostructure is more uniform, but the grain size is somewhat coarser.
The location, number and growth rate of nucleation are related to the composition and cooling condition of the alloy [14-15].
The crystal nucleus firstly forms at the grain boundary and grows into a net grain boundary a.
Relatively deep, uniform and higher number dimples can be seen in the tensile fractography of the tube billet extruded at 820℃, which has obvious ductile fracture feature, as shown in Fig. 4a2.
COLLINS, Formation of grain boundary a in b Ti alloys: Its Role in Deformation and Fracture Behavior of These Alloys, Metall.

Since we would like to reduce the number of parameters in the optimization process, the main numerical difficulty of this problem is to find a mesh free method to describe a domain partition and then to develop a numerical method for the minimization of the partition dependent plastic dissipation functional, that avoids, as much as possible, local minima.
Finally, the proposed algorithm consists in the following principal ingredients: description of the set with a small number of parameters, description of the vector field, reconstruction of the topology of the set and the computation of the cost function.
The same number of voids (i.e. with the same porosity) but with a different distribution will give a different fracture surfaces and different limit loads.
The second heterogeneity concerns rigid grains (black spots in Figure 2 right), which is included in the DVDS modeling through by considering C(x,y) very large on the rigid grains.
Left: homogeneous (grey); Middle: voids (white) heterogeneity; Right: rigid grains (black) heterogeneity.

Table 1 Hardness under the different deposition time Test number Deposition time [min] Micro vickers hardness [HV0.1/10] 1 5 345.23 2 10 353.88 3 15 310.20 4 20 333.38 5 30 285.24 6 Original group 282.59 Table 2 Friction test result Test number Deposition time [min] Initialweight, M1 [g] Final weight, M2 [g] Wear quality, △M [mg] 1 5 86.2806 86.2785 2.9 2 10 86.2321 86.2287 3.4 3 15 86.2789 86.2749 4.0 4 20 86.2109 86.2056 5.3 5 30 86.2871 86.2807 6.4 6 Original group 86.1641 86.1594 4.7 Fig. 1 Relations of hardness and deposition time.
The reason is that the concentration of the atoms or atom groups between the sputtering target and the substrate increases when the sputtering power turns higher, as well as the atomic collision probability, which leads the power of the atoms decreasing that makes the ability to move on the surface of the substrate weaker, and in this condition the sputtering of sedimentary particles take the dominant mechanism in the growth of the grains which leads the grain sizes of the coated membrane layers increasing, however the number of the grains decreasing as well as the intensity of the thin films.

The scanning speed of laser beam (mm/s), the resolution in pulses per inch (ppi) and number of heating cycles (NC) to be used in this experiment were selected from previously tests conducted by [7].
Table 2: Parameters of the lasers processing Samples Speed [mm/s] Resolution [ppi] Number of cicles P1 40 300 5 P2 60 300 5 P3 80 300 5 Fig. 3: Experimental set-up.
The parameters used in the test were: linear velocity of 10cm/s, the track radius of 5mm, 52100 steel balls with 6mm diameter, number of rounds equal to 2000 and load equal to 5N.
The results obtained by AFM indicate a possible crystallization of carbon black, grains coalescence and the appearance of new phases from the process of heating by laser, as shown in Figure 8.
The roughness tests evaluated by AFM, presented a heterogeneous results ranging RA= 87.999nm to RA= 124.115nm, that could be associated to the grains coalescence on the samples surface.

One of the methods is associated with an increased number of nucleation sites due to refractory inclusions in a specific physical, chemical, structural and size agreement with the base metal.
The application of the modification method by entering refractory particles in melts can change the grain of the alloy and improve both mechanical and operational characteristics of materials [1].
Comparing the values of the average particle sizes of the initial powders and particle sizes in the briquettes of both powders after pressing and sintering does not lead to a considerable change of the average particle size, thus, coagulations of grains is not observed.
The rise of microhardness is observed with the porosity less than 30% after pressing, so compacting of material is accompanied by the deformation of grains [9].
In this work sintering was carried out at low temperatures in order to avoid the collective recrystallization of particles and deep sintering of the entire pressing, and only burning of the powder particles in the surface layers of the briquette in order to preserve the strength of grains, to decrease the mobility of grain boundaries and to prohibit chips on grains [14-16].

The microstructure of this alloy consists of α-Mg matrix and interdendritic compounds distributed at grain boundaries.
The number of data points is not sufficient to evaluate Qs.
After creep test at 200°C grain boundary voids are present in the AJ62 alloy (Fig. 5a).
In the interior of grains of AJ62 magnesium alloy, subgrain formation and decreasing the dislocation density are observed (Fig. 6b).
The dominant creep mechanism at 60-75 MPa and at 175°C is grain boundary sliding.