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.% Al2O3 abrasive with W10 grain size and de-ionized water, and (3) substrates lapped with slurry consisting of 10wt.% Al2O3 abrasive with W2.5 grain size and de-ionized water, corresponding to the processes of the MgO substrates preparation before polishing at present.
The dislocation slip layer under the fracture layer is composed of large numbers of dislocation pits.
The dislocation slip occurs on the easy slip planes under the intense shear stress caused by the grains in machining process.
In fine lapping process, the load of abrasive grains on the surface is smaller than the critical load leading to the cracks, so there is no formation of cracks and fractures.

Introduction Currently there is lot of interest pertaining to processes involving Severe Plastic Deformation (SPD) as these processes offers the possibility of production of ultra fine grained microstructures in bulk quantities.
In this approach large amount of plastic strain is imparted to a specimen to produce an ultra fine grained high strength material.
The initial average grain size of the material was found to be 50µm.
Further work is underway to establish the effects on workability after larger number of ECAP passes and other processing routes.
In the annealed condition, the average grain size was 50 µm and after the first pass and second pass ECAP, it reduced to 25 and 14 µm respectively.

So, collect a large numbers of information during the initial process, and run the flow path of collect, register, integrity check, reliability check, classify, preparation by screening sift, coding, clear up and the final one is filing.
After random selection of 10% of the evaluated unit in the classified cultivated land to conduct grain output investigation, it is shown that: the average output of the second grade land is 750 to 800 kg per unit of area by using integration index method and accumulated frequency curve method, it should be classified as third grade land in nationwide grade; the average grain output of the third grade land is 660 to 700 kg per unit of area, it should be classified as fourth grade land in nationwide grade; the average grain output of the fourth grade land is 550 to 600 kg per unit of area, it should be classified as fifth grade land in nationwide grade (table 14).
Tab.7 The Cultivated land quality evaluation analysis results table Nationwide grade 1 2 3 4 5 6 grade of JY city 2 3 4 Grain productivity (kg/a unit of area) ≥900 800-900 700-800 600-700 500-600 400-500 Analytic hierarchy model is used during cultivated land evaluation process to establish the evaluation index system of the cultivated land productivity.

The each number in the parentheses is the maximum thicknesses of each film.
From AFM images seen in Fig. 6, the grains of a few micro meters were observed on the surface of the sample annealed at 800 and 1000 oC.
It was found that grain size and average surface roughness (Ra) increased with increasing annealing temperature.
The grain growth caused by the annealing at 800 oC is considered to effect the improvement of crystallinity.
On the other hand, for the annealing at 1000 oC, grain was large and assumed to contain larger concentration of defects compared with the annealing at 800 oC.

This is partly due to the external morphology of the pozzolana grains.
This difference lies in the grain outer shape that can be spherical Figure 1 and else to the presence of some finer further increasing these properties.
This is partly due to the external morphology of the pozzolana grains (this difference lies in the grain outer shape that can be spherical) and partly to the presence of some finer further increasing these properties.
The latter give the composite a large number of applications some of which are of a high technological level.

The Additive Manufacturing (AM) of small and medium-sized Ti–6Al–4V parts represents an interesting business case for a number of industrial applications.
Bottom (HAZ) Middle Top Fig. 4 – Optical micrographs of the cross section of two layers of Ti-6Al-4V weld sample showing (a and a’) top, (b and b’) middle and (c and c’) bottom of the layers (HAZ) Fig 4 (a)-(c) indicates formation of columnar β grains which shows considerable increase in grain size from the bottom to the top edge of the deposition.
This has been attributed to the rate of solidification during the process, where precipitation of directionally oriented Body Centred Cubic (BCC) β grains has been observed.
This type of microstructure (Widmanstatten type or Basket-weave type) has been reported by previous researchers as a results of precipitation of α phase within the β grains due to rapid cooling cycles during the process [9].

The aim of these processes is to introduce high values of deformation inside the parts in order to reduce the grain size and thus to improve the mechanical properties of the starting material.
This is achieved by means of the reduction in the grain size up to micrometric or even nanometric values [1].
In the table, DF represents the number of degrees of freedom.
In elements, the number of nodes in the cross-section is approximately 280 whereas the number of positions studied for the evaluation of microhardness is, as was mentioned, 32.
Nevertheless, this can be only carried out a specific number of times until the fracture of the material occurs.

RESULTS AND DISCUSSION Precipitation OM and SEM examinations of the spiral wires and cross-rods from belt B1 operated in the standard furnace atmosphere and belt B2 after service in the modified atmosphere revealed precipitates on grain boundaries and within grains.
SEM/EDX microanalysis revealed that the particles on grain boundaries and within grains consist of chromium and carbon, or chromium, carbon and nitrogen, or chromium and nitrogen, which indicates that they are chromium or chromium-rich carbides, carbonitrides, or nitrides.
The internal oxidation depth is highest in the areas containing silicon oxide that was formed along grain boundaries.
The amounts of chromium-rich carbides, nitrides or carbonitrides on grain boundaries and within grains depend on the carbon and nitrogen contents of the material.
Even though the average elongation of the B2 cross-rods was higher than the corresponding value of belt B1, the difference in elongation is not statistically significant, which may be related to the low number of test samples.

One of the most successfully and frequently used ceramic material is boron carbide B4C, which has a number of unique properties.
A pore free microstructure consisting of B4C grains surrounded with fine grains of (Ti0.9W0.1)B2 and W2B5 formed due to WC contaminations was obtained.
It was shown that formation of boron carbide in the presence of WC, WC–Co and Co promotes sharp reduction in its grain size.
Korkia, Synthesizing fine-grained powders of complex compositions B4C–TiB2–WC–Co, Solid State Sci. 108 (2020) 106439 (1-8)
Chedia, Method of obtaining multicomponent fine-grained powders for boron carbide matrix ceramics production, Mater.

Constitutive computations are carried out on two aggregates of FCC crystal grains, with each representing one of the two zones, respectively.
Key words: forming limit diagrams, crystal plasticity, M-K approach 1 Introduction The formability assessment of sheet metal has been one of the research fields for both mechanical engineers and metallurgists over the last fifty years [1-24] , in which a number of theoretical approaches have been proposed for the determination of forming limits diagrams (FLDs) and to explain the localized necking in biaxial tensile test.
They first derive analytical expressions for predicting FLDs corresponding to ideal crystal grain orientations and then perform numerical calculations of FLDs for polycrystalline aluminum sheet metal with initial texture.
It is postulated that a groove will be formed in aggregate of grains with similar crystallographic orientations that are different from the bulk of the sheet.
In all the calculations, 500 grains are employed both inside and outside the groove.