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The deterioration of the cutting edges of the abrasive grains is initially large and hence excessive force was recorded [1].
This was due to the fact that, as the feed speed for dressing increased, the abrasive grains hence generated were distantly spaced from one another and the number of abrasive grains that would actually perform cutting operation was reduced.
When the grinding wheel and work come in contact, the abrasive grains impacting the work and hence the sensor, the rate at which the abrasive grains attack the work is picked up.
Fig. 10 Frequency variation with respect to dress pattern Thus, the number of times each of the abrasive particles strike the work is altered as the dress pattern is altered.
This phenomenon is due to the fact that the number of abrasive particles that come in contact with the work increase when the dress pattern gets fine.

Where N is the number of test samples, is the measured data, is The results predicted by the model.The results are shown in Table.6 Table.6 Results Term RSM Model 94.921％ 7.05％ 6.08％ From the above results, the predicted result of RSM model has the forecast effect and good engineering practice significance.
When feeding speed is small, the number of abrasive grain that per unit time through the grinding zone is increase, namely increase the number of cutting edge, so the grinding amount is very large[12-14].
But as the feeding speed increases, single abrasive grain in the grinding zone cutting time is shortened, so the grinding quantity reduced gradually.
The causes of this phenomenon are as follows: This is because with the abrasive belt speed increase, the unit time to enter the number of abrasive grain grinding area increased, but the grain cutting depth becomes small, the surface of the metal deformation is small, but also shorten the workpiece and abrasive contact time, reduced because of metal abrasive tillage ridge height plough formation and thermal plastic deformation, thus roughness decreases.
The causes of this phenomenon are as follows: with the particle size of the belt increases, fine abrasive grains in the cutting edge generated during processing scratches and ridges corresponding reduced, so the lower the surface roughness.

This mismatch causes the formation of a layer, which differs in depth and in the size of the formed grain.
Due to the inhomogeneity in the depth and due to the great number of the grain, the inhibition layer is destroyed selectively giving rise to an outburst formation of Fe-Zn phases (Fig. 2).
Number 1 refers to outburst formation.
Amongst them the diffusion of zinc through the inhibition layer combined with the precipitation of oxide at the grain boundary of the inhibition layer, seems to explain sufficiently the breakdown of the Fe2Al5 layer.
Number 1 refers o the ZnFe phases.

The average grain size of the aluminium is about 50-55 µm measured using a linear intercept method.
The average grain size of aluminium in surface composite is less than 5 μm.
The grain refinement can be attributed to the pinning effect of Al2O3 and SiC particles which impede the grain growth by suppressing grain boundary sliding.
Reduction in size of SiC particles intensifies the pinning effect of the particles and increases the breakup of pre-existing grains, which leads to decrease the grain size severely [11].
In Fig. 3b, the minimum number of sharp edges was found compared to as received SiC particles in the surface composite and less than 5 µm in size.

Arrows and dots show the minimum concentrations found in different grain types found in billets cast at 80 mm/min (CC-coarse-cell grain; FC-fine-cell grain; Fragm.
Both grain-refined (GR) and non-grain refined (NGR) alloys were tested.
The results shown in Figure 3 clearly demonstrate that coarse-cell grains, fine-cell grains and less developed dendrites (found in grain refined 7075 alloy) have been formed in different parts of the sump as depicted in Figure 1.
Second, the coarse-cell grains are formed in the upper part of the solidification range, possibly above the coherency isotherm, which can be rather low in grain refined alloys.
These grains contribute to the negative centreline segregation.

And we calculated out the average grain-size of sample according to the breadth of diffraction peak and the line broadening formula.
When we analyzed infrared absorption spectra in lower wave number (Fig.3), we could see there was a main character infrared absorption peak at 416 cm-1, which was Mg-O libration’s main characteristic absorption peak.
Based on relevant lattice geometry knowledge and formulas, XRD data, and the formula between diffraction peak width and line broadending D=0.89λ/B, we worked out the average grain size of sample ,shown in Table 1.

The flank wear of CBN inserts were measured after predetermined number of passes.
Scanning electron microscopy images show that on the flank surface of the tool small holes appear in such places that were previously occupied by CBN grains, which show that the CBN grains pluck out from the tool surface due to adhesive wear.
Thanks to the plucking out the edge of tool is continuously renewed during cutting, because from the deeper layers of flank wear land sharp grains come into the surface continuously [4, 7].
During the cutting after a predetermined number of passes optical microscopy images were made with Zeiss discovery V8 optical microscope of the worn flank surface and edge chamfering and the flank wear of cutting inserts were measured.
Szabó, Stability Criteria and Break out of Grains of Super-Hard of Grinding Tools, Journal of Materials Processing Technology.

The micrograph reveals homogeneous and densely packed grains with mean grain size of 200 nm for the thin film deposited for 20 minutes.
However, the surface becomes rough and the grains grow larger for the film deposited for 120 minutes.
The results indicate that the grains grow larger with increasing deposition time, therefore the formation of rougher surface and larger grains for the films deposited for long time in the same deposition condition.
Fig. 6 Cyclic voltammograms vs. cycle number for Li4Ti5O12 film deposited for 120 minutes.
The impedance increases with cycle number before 20 discharge-charge cycles, then keeps a steady value.

The researchers found that the reduction in grain size increased the crack growth stress along with the critical stress intensity factor (maximum at grain size 11.65nm).
The researchers suggested that the change in crystal orientations and form of grain boundaries can blunt the crack.
These samples are replicated in order to increase the number of atoms.
The total number of atoms in the system is 72726.
NVT thermodynamic ensemble (N=number of atoms, V=Volume, and T=Temperature are constant) is used for our system.

Yang et al. applied PMF during the solidification of Mg-Al-Zn alloy and Al-Cu alloy, and the primary α-Mg grain and eutectic structure were refined [4,5].
In contrast, the microstructure of Mg93Zn6Y alloy treated by PMF which consists of majority of primary α-Mg grains with fine rosette-like morphology, as shown in Fig.2 (b), and the average diameter of primary α-Mg grains were about 102μm.
In the case of PMF, the initial solidified many nuclei forming on the wall of the mold in a heterogeneous nucleation pattern were easily broken off by forced convection and would be transported into the entire liquid metal [4].Thus, the number of nuclei in the melt was increased.
It can contribute to increasing the rate of heat transfer and the removal of liquid superheat [7], which decreased the likelihood of remelting of initial solid grains.
Moreover, fragmentation, nucleation and growth could happen within the entire melt, which gave rise to the refinement of grains throughout the bulk liquid.