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In substituting the real experiment data, a verification experiment for the machining volume and grain wear forecast of concrete diamond grinding tool was conducted using grinding parameters as input value and machining volume and grain wear as output value.
The example result indicated that the model can precise forecast them machining volume and grain wear of diamond grinding tool.
The general form of a grey model is, in whichis progression of grey differential equation andis the number of the variable [3].
Experimental condition and method To gain information about the fundamental correlations between process parameters and work piece specifications, experimental data about the single diamond grain scratch tests in grinding concrete.
Table 2 Comparison between real value with simulation value on cutting speed factors test serial number 1 2 3 4 5 6 7 8 test value（） 0.9058 1.9928 2.3551 3.7699 5.1836 6.1261 8.3744 9.8971 simulation value（） 0.9058 1.8752 2.5696 3.6331 4.9664 6.4914 8.1556 9.9323 absolute error（） 0 0.1176 -0.2144 0.1368 0.2173 -0.3653 0.2188 -0.0352 relative error（） 0 0.0590 -0.0910 0.0363 0.0419 -0.0596 0.0261 -0.0036 Table 3 Comparison between real values with simulation value on machining volume factors test serial number 1 2 3 4 5 6 7 8 test value（） 14.2510 29.1205 32.2741 33.8378 35.2210 38.5427 39.5514 43.9126 simulation value（） 14.2510 29.3072 31.9664 33.8704 35.5506 37.4730 40.0140 43.4698 absolute error（） 0 -0.1867 0.3076 -0.0326 -0.3296 1.0697 -0.4625 0.4428 relative error（%） 0 -0.0064 0.0095 -0.0010 -0.0094 0.0278 -0.0117 0.0101 Table 4 Comparison between real values with simulation value on diamond grain wear factors test serial number 1 2 3 4 5 6 7 8 test value（） 0.0050 0.0100 0.0060

To ensure a micro hole is drilled within a grain or on the boundary of grains, the diameter of an electrode should be less than the average size of grains.
The total number of micro holes drilled is 107.
In this study, the number of micro holes drilled within the grain is 56 and 51 on the boundary.
During the formation of a grain in alloy, a particle with the highest melting temperature solidifies firstly, forming a nucleus of grain.
Fig. 7 shows the distribution of discharge gaps of machining within a grain and on the boundary of grains.

Partial ring cracks are a particular crack type when grinding with large-size and blunt diamond grains.
Median cracks will cease to form after the grain depth of cut is below the critical depth of cut [7].
Median cracks are the only crack type, which existed in a small number of local regions.
Since the specimens were fine chemical mechanical polished silicon wafers with a surface finish 0.3nm in Ra, and no surface and subsurface damage existed before single grain grinding, any possible damage was induced by single grain grinding.
The deep narrow valley was an embodiment of the subsurface cracks induced by single grain grinding.

Experiments with a number of different steels show that the methodology can be applied to sheet of different formability.
At such high levels of local deformations, grains are elongated extensively and the grain boundaries are severely disrupted.
The 3D nature of the grains that are elongated towards the fracture surface can be clearly observed.
For IF steel, for example, triple grain boundaries are observed to be probable nucleation sites (Fig. 6(b)).
Experiments with a number of different steels show that the methodology can be applied to sheet of different formability.

The grain size and chemical compositions of the raw material are investigated.
The grain size composition of ash from Tomsk ash-disposal area is detected by the air-dried raw material sieve residues.
The lesser water amount is absorbed the larger number of freeze-thaw cycles the product sustains.
Colloidal adhesive forces are observed at the increase of microdisperse particle growth (> 3 μm) in the original material, the number of which increases in dispersed non-fuel ashes.
Velosa, Spent brewery grains for improvement of thermal insulation of ceramic bricks, J.

The number and the average misorientation of the directional boundaries tend to increase with strain, leading to the subdivision of original coarse grains into different orientation regions and, finally, to the development of fine equiaxed grains at high strains.
The alloy had a grain size of ~80 mm.
As a result, most of crystallites being true grains are entirely delimited by HAGBs.
A further temperature increase leads to the formation of a mixed structure; coarse (sub)grains alternate with grains (Fig. 1e, 1f).
At 375°C, the mobility of LAGBs is so high that only a limited number of grains having an equiaxed shape form.

In FSP, the material undergoes intense plastic deformation, yielding a dynamically recrystallized fine grain structure.
Recent studies showed that refining the grains of magnesium leads to significant enhancement in its formability [12, 13].
Changing the number of hidden layer and/or the number of neurons per hidden layer may alter the predictions obtained, different runs where performed with different transfer functions, number of layers and number of neurons in the hidden layer.
A maximum number of 1000 training epochs was maintained for all runs.
At higher rotational speed more frictional heat is produced, which means more grain growth and as a result less hardness.

This is facilitated by dislocation slip across the grains leading to the formation of pile-ups at adjacent grain boundaries [5,6].
It is proposed that this metallurgical condition can be satisfied by the material possessing a significant number of high angle grain boundaries, as these allow easy climb of dislocations at boundaries.
A number of microstructural and thermo-physical parameters need to be specified for numerical integration of Equation-set (3)-(10).
The influence of grain size is also shown.
Illustrates the effect of grain coarsening (evaluated at 900oC).

One is the theory of anisotropic grain boundary number, which was propounded by Coble [10,11].
In the former theory, the grain boundary number per unit length influences sintering shrinkage, because mass transport to neck occurs along grain boundary during sintering.
According to the grain boundary number theory, even spherical alumina particle compact aligned should hold isotropic sintering shrinkage, because the grain boundary number is isotropic in the compact.
The grain boundary number theory can not explain the sintering shrinkage anisotropy of spherical alumina particle compact with particle orientation.
However, this study does not exclude importance of the grain boundary number in ceramic compact on the sintering shrinkage anisotropy.

Too much or too less of dopants (both Pr6O11 and TiO2) in the varistor cannot obtain regular shapes of ZnO grains, and the grain boundaries are neither clearly observed.
The results reveal that the Pr- and Ti-rich phases were distributed at grain boundaries, triple point junctions or embedded in ZnO grains, which is an inhibitor for ZnO grain growth.
The inhibitors for ZnO grain growth include the secondary phases PrTiO3 and Zn2TiO4, and the praseodymium ions segregated in the region of grain boundaries [8].
The increase of varistor voltage can be explained by the increase in the number of grain boundaries owing to the decrease of the average ZnO grain size [9].
This is attributed to the increase of the number of grain boundaries caused by decreasing average ZnO grain size.