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However, only less than 1% of the added TiB2 particles are active for nucleation of α-Al grains [6].
Experimental Properties requirement of aluminium sheet for automotive application are met largely by a number of Al-Mg alloys (5xxx series) .
The line intercept method was used to measure the grain size along the transverse section.
Enough numbers of the potent oxide particles as nucleation substrates can enhance the heterogeneous nucleation throughout the whole melt volume, resulting in grain refinement as seen in Fig. 2.
Greer, Control of grain size in solidification, in: B.

During storage, a number of physicochemical and physiological changes occur, this is usually termed ageing.
However, the respiration rate of grain is lower than fruits or vegetables, so MAP was not so significantly action for preserving grain fresh.
At maturity, rice grain was random harvested.
After drying, grain was stored at room temperature for 5 months, maintaining about 14.3% of moisture.
According to the results, the big hermetic plastic tent was good for rice grain flavor preserving.

For a number of alloys based on titanium nickelide the effect of SRQ on the internal structure, grain refinement, and amorphization has been considered.
The number of such orientations can be only 12.
First crystals that have appeared in the grain of an initial phase determine in a considerable extent the further course of MT not only in the given but also in adjacent grains.
Crystallographic texture is provided via employing quite a number of ways [6-11].
Employment of several passes by different optimum technological routes made it possible to create in these alloys the nano-structure highly uniform uni- or bi-modal grain–subgrain state with average grain sizes close in value to 100–200 nm (Fig. 21).

The larger, elliptoid M23C6 particles mainly precipitate on prior austenite grain boundaries and sub-grain boundaries, while the finer spherical MX particles are precipitated on the dislocations within martensite laths.
The M23C6 particles precipitated on the grain boundaries are elongated along the grain boundaries direction, in which diffusion coefficient relatively high.
Therefore, with the temperature increasing, M23C6 and MX particles which begin to coarsen and dissolve in matrix, can not cause an effective pinning on the grain or sub-grain boundaries and dislocations.
Moreover, in this two-step tempered sample, the size of laths width and precipitates is lower than that of sample S2, while the dislocations density and precipitates number is higher than the latter.
These particles precipitated at early stage can pin the grain or sub-grain boundaries and dislocations, retarding recovery of which at a higher temperature.

In order to clarify this problem, it is advisable to perform experimental research under conditions where the number of 'free parameters' affecting this transformation is minimized.
The range of potential disorientation angles was binned into intervals of 1.25o into which the number of disorientations across the recrystallization front corresponding to a given angular interval was counted.
The columns contain the explicit number (‘Counts’) of experimental axis in a class and the fractions after accounting for the differences in the areas of regions and the impact of crystal symmetry (‘Distr.’).
The results allows us to draw the following conclusions: · For Ni and Cu-2%Al and both initial orientations at the initial stages of recrystallization, the appearance of a specific number of new orientation groups of new grains was demonstrated.
This facilitates ‘the orientation stability' of a new grain growing into the as-deformed structure

In specimens were examined the sizes and number density of carbides, the prior austenite grain size and the fineness of the resulting hardening-type microstructure.
Size and Number Density of Carbides.
The smaller was the size of carbides in the microstructure, the greater was their number density.
The prior austenite grain size is related to the number density of carbides in the matrix.
Prior austenite grains were polyhedral in all specimens.

The optical micrographs reveal the formation of fine grains.
Thus, a fabrication process is required with proper parameters to increase the interfacial bonding strength and to decrease the number of pores and thus mechanical properties will be improved.
Densification for ECAPed specimens increases with increase in milling time along with number of passes.
As, the number of passes increases for the20hr and 35hr milled powder, the hardness increases significantly.
Langdon, The principles of grain refinement in equal-channel angular pressing, Mater.

The distribution of d¢ phase distribute more homogeneously in the grains.
The properties of Al-Cu-Li alloys are determined by the structure, including the macrostructure, such as texture and grain shape, as well as microstructure, such as the type, size, number and distribution of precipitates within the grains and at the grain boundaries[7,8].
Electron back scattering diffraction technique was applied to investigate the grain size, grain shape and misorientation angle distribution using JEM-7001F.
With the increase of compression deformation, the number of the precipitats increase firstly and then decrease, and the size of precipitates increase gradually.
The influence of grain structure on the ductility of the Al-Cu-Li-Mn-Cd alloy 2020.

The grain size decreased with increasing strain rates at 750k. 1.
The microstructure consists of elongated grains with serrations developed in the grain boundaries and newly formed equiaxed grains of different sizes, indicating dynamic recrystallizatioin (DRC) occurred during hot compression deformation at strain rate of 0.01s-1 (Fig3(a)).
The coarsening of precipitation phases at grain boundary could pin the grain boundary, and prevent it from fast migration, so both the newly formed recrystallized grain and old grain would not grow very fast.
That is why the grain size decreased with increasing temperature at 750k.
Acknowledgement It is a project supported by natural science foundation of shanxi province China (project number: 2009011028-1; 2011011021-1).

The model of abrasive grain’s wear.
Abrasive grains move at a constant speed.
Fig.3 The relationship between grinding force and surface roughness The reduction of surface roughness is directly related to the number of active grains Ng and the shape of the grains.
Under these conditions, abrasive grains are worn quickly or can be extracted from the bonding phase which may decrease the number of real active grains Ng.
New grains are involved in grinding.