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This failure was largely caused by the nucleation, propagation of a large number of micro-cracks inside the work piece under the action of grinding force.
crack crack a) common grinding b) f=20kHz, A=16.41μm crack b) f=20kHz, A=16.41μm c) 45kHz, A=13.57μm Fig. 2 Effect of ultrasonic frequency on surface microtopography of ZrO2 ceramics under the two-dimension ultrasonic vibration grinding (Vw＝0.25m/s, f＝2mm/r, ap=5μm, grain Size: 270#) From Fig. 2 (a), it can be seen that the more surface defects under common grinding conditions and Material fracture phenomenon is serious than ultrasonic vibration conditions, in addition, many "horns" crack produced along the direction of grinding scratches because of the effect of friction force between grinding grit and grinding, as shown amplification part in Fig. 2(a), and most of this kind of crack extend to the direction of grinding, while this kind of crack did not appear under ultrasonic grinding.
crack crack crack a) 35kHz, A=14.94μm b) 35kHz, A=4.23μm Fig. 3 Effect of amplitude on surface micro topography of ZrO2 ceramics under the two-dimension ultrasonic vibration grinding(Vw＝0.25m/s, f＝2mm/r, ap=5μm, grain Size:270#) Fig. 3 is surface microstructure of ZrO2, which frequency is 35 kHz with different amplitude under two- dimensional ultrasonic grinding.

Thus, an important objective of any rapid solidification process is to produce a solid of uniform composition, with increased solid solubility of alloying elements, a significant decrease in grain size, and possibly with formation of metastable crystalline phases or production of non-crystalline phases [8].
Figure 1 shows differences in the surface appearance of atomized particles: smooth surfaces were observed in smaller particles than 45 mm and rough surfaces were observed in larger particles and can be related to coarse equiaxed dendritic structures, as well as by presence of micro-contractions in the surface of the powders (Figs. 2a-b), suggesting that large particles solidify with lower undercooling thus presenting a low number of nucleation sites [9].
It is noted that the atomized particles suffer considerable deformations during extrusion and they are accommodated with an appearance of equiaxed grains.

Its use in high-mobility concrete mixes allows obtaining heavy and fine-grained concretes with the strength of 70-140 MPa (depending on concrete composition) with the high speed of curing.
W/C; kind and number (%) of chemical additives Compressive strength of concrete, MPa Without care, days Normal conditions, 28 days 1 3 7 14 21 28 W/C=0.38; Sikament® BV 3M – 0.7% 16.5 21.9 21.7 20 22.1 24 54 W/C=0.37; Sikament® BV 3M – 0.7%, NMP – 0.04% 18 25 26.4 26 30.6 36.5 47.5 W/C=0.36; Sikament® BV 3M – 0.7%, Xiameter® MHX-1107 – 0.04% 11.4 17.3 22.6 25 27 29.8 55 W/C=0.36; Sikament® BV 3M – 0.7%, NMP – 0.04%, Xiameter® MHX-1107 – 0.04% 10.1 23.6 24.5 25 25 27.1 52.4 Note: NMP – nitrile-methyl-phosphoric acid; Sikament® BV 3M – plasticizer; Xiameter® MHX-1107 – polymethylhydrogen siloxane fluid.
Kardumyan, Modified high-strength fine-grained concretes with improved deformation characteristics, Conc.

material dropping interval TJ1 690 625 640 770 210 TJ2 710 710 710 675 230 TJ3 695 760 745 650 250 TJ1v 230 208 213 257 200 TJ2v 237 237 237 225 280 TJ3v 232 253 248 217 230 RJ 7 45 35 40 215 TJ1：Represent various factors 1 horizontal sum；TJ1v：Represent various factors 1 horizontal mean value；RJ：Represent Xmax-Xmin 190 270 LJ reducing agent for cement XB results are shown in Table 9： Table 9 LJ for XB initial flow test results: Calculation analysis Factor A Factor B Factor C Factor D The initial liquidity The stir of bottom material Temperature A material continuously dropped B material dropping interval TJ1 530 540 545 560 160 TJ2 580 575 540 530 160 TJ3 585 580 610 605 210 TJ1v 177 180 182 187 190 TJ2v 193 192 180 177 210 TJ3v 195 193 203 202 180 RJ 18 13 21 25 190 TJ1：Represent various factors 1 horizontal sum；TJ1v：Represent various factors 1 horizontal mean value；RJ：Represent Xmax-Xmin 190 270 In Table 4-Table 9,bold numbers
System differences may performance in cement particle size distribution, grain type , which is the physical aspect,and the impact of accessory types and chemical composition in the production process of ordinary Portland cement,which can by adding to mixed material to adjust the gradation and reduce the impact of cement materials composition.
(2) The results showed that there are system differences exist in the adaptable of different cement Polycarboxylate superplasticizers[7],these differences caused by the physical and chemical properties, graded cement particles, grain types and the types of accessories all have an impact

As a result, the impact of flap abrasive grains on the surface of the contact spot will differ significantly, which leads to uneven metal removal along the processing width.
The best quality of grinding will be achieved when this gap is completely eliminated, since in this case the impact of the flap wheels on the contact surface will be the same both in terms of the impact force and number of abrasive grains.

Specific gravity 1.06 ± 0.01 pH 6 ± 1 Chloride content < 0.1 % Alkali content ≤ 1 % Dry extract 30,2 ± 1,3 % Sand Bechar City (southwest of Algeria) benefit of a large number of building materials, the main choice is the nearly site, the used sand is the principal existing sand in this region.
It is remarkable to notice, the use of rolled SCM seems permit the flow of aggregates grains between themselves by slip between rolled SCM.
Even if crushed SCM is used the grains aggregates slip between themselves not by their morphology but by dispersion of fine limestone by superplasticizer dispersion action (rheological despersion).

The grain size, D, in the thin films was estimated from the half-widths b, at the maximum of the or the XRD peak with the highest intensity by using the Classical Scherrer formula, assuming that microstrain were neglected.
The powdered particles of diamond were obtained when as-prepared graphite powder was annealed at 1350 ºC, which was in well match with JCPDS file number (JCPDS 89-3439) cubic structure of lattice constant a = 3.567 A0, the predominant peak is 111 plane with minimum intensity of the spectrum.
The gas sensitivity is relative to grain size, surface state, oxygen adsorption and lattice defects.

The technique yields two effects during the gas injection, vigorous agitation and rapid heat extraction, so that a number of fine globular grains are created just a few degrees below the liquidus temperature.
Representative microstructures of the commercial plate at four different positions, shown in Fig. 7 (a), appear to have different grain features and sizes.

In order to improve the wetting property of the melted powder, the plate surface was sandblasted with #35 of average grain size[5].
The thickness of the beam model which was varied by the number of forming layers was ranged 1 - 30 mm.
Fig. 6 showed the influences of the layered number on the base plate deformation and the residual stress at the consolidated surface under the base plate height of ts=20 mm.
The deformation height and residual stress increased with the increase of the layered number, and then became almost constant when the layered number was over 400 layers.
The increase of the residual stress was due to the increase of the consolidated layer, which was equal to the laser irradiation number.

The researchers used a high-frequency solid-state laser with a wavelength of 1.06 μm and continuous radiation of a gas laser on carbon dioxide with a wavelength of 10.6 μm to break the metal bond, remove adhering chips, level the profile, control the protrusion of abrasive grains, and profile circles.
Naming and designation of factors Levels of variation Intervals of variation – 0 + Processing speed [mm/s] 10 15 20 5 Radiation power [W] 40 50 60 10 Let's introduce designations: х1 is processing speed; х2 is radiation power, which are coded factors, varying at two levels; N is number of experiments; j is the number of the experiment (j = 1, 2,…, N); n is the number of repeated measurements in the j-th experiment; y is the response function; is the average value of the response function.
Since the number of factors is small (two), it was decided to conduct a full factorial experiment of type 22, where the number of factors k = 2, the number of levels p = 2, the number of experiments N = 4, and the number of repeated experiments n = 5.
With the same number of parallel experiments for each combination of factor levels, the reproducibility of the process (the absence of significant deviations) is determined by the Cochran criterion.
(7) The value of the Student's coefficient t (P; fE) for the confidence probability P = 0.95 and the number of degrees of freedom fE = N × (n – 1) =16 was taken from [16].