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The nanohardness of Co binder was approximately 10 GPa and that of WC grains varied between 25 and 50 GPa, depending on the grain orientation and load.
A number of studies have been devoted in the past to the characterization of the effect of microstructure of WC – Co systems on their hardness and the effect of crystallographic orientation of WC single crystals on hardness [2 - 3].
A decrease in hardness with the load increase was found in all indented WC grains.
The nanohardness of Co was approximately 10 GPa and the hardness values of WC grains were in interval from approximately 25 GPa to 50 GPa depending on the orientation of grains.
The EBSD analysis Fig. 3, revealed that the triangle shaped WC grains are close the the basal and the square shaped WC grains to prismatic orientation, respectively.

Samples were obtained from the middle portion of the rolled blanks in the number of 3 pieces for one test.
The boundaries of the grains and intergranular delamination, specific to corrosion, are not observed.
Results and discussion On the grain boundaries, dispersion phases can be seen (nanophases of 90 – 200 nm size, see Fig. 6).
In the melt №3 sample, allocating nanoparticles are visible not only at boundaries of grains and blocks, but also inside the grain, which is typical for Mg2Si phase.
The preferred structure of welding seam area using weak pulsed current (WPC) is presented in the samples of melts number 2 and 4, structure of melts number 1 and 3 has defects, but in general microphotographs demonstrates, that microstructure is fine-grained (1 – 10 μm). 2.

These grains are more rounded in the case of AXJ530-ESTC specimens than for the AXJ530-SFTC.
(b) AXJ530 SFTC2 1&2 98.39 1.42 - - - α-Mg 3 75.72 12.17 9.72 - 2.97 Sr-rich particle 4 75.89 15.21 8.71 0.07 0.09 α-Mg + (Mg,Al)2Ca 5 1.93 52.47 0.09 43.16 - Mn-Al 2 See Figure 2c for spot numbers.
(c) AXJ530 ESTC3 1&2 98.39 1.48 0.06 - - α-Mg 3 76.12 14.60 9.14 - 0.06 α-Mg + (Mg,Al)2Ca 4 78.90 10.59 4.97 - 5.13 Sr-rich particle 5 30.79 42.80 25.77 0.32 0.11 α-Mg + (Mg,Al)2Ca 6 2.45 55.65 0.15 41.73 - Mn-Al 3 See Figure 2e for spot numbers.
However, after 60 minutes of immersion, severe corrosion occurred at grain boundaries as well as within the grains.
On the other hand, the two thixocast specimens were composed of large grains of pre-existing α-Mg phase and a fine microstructure, similar to that of the die-cast specimen, composed of finer α-Mg grains and eutectic constituents.

Experimental Procedures Cylindrical rods of Zirconium 9 mm in diameter were subjected to ECAP by routes C and BC at 350 oC with the number of successive passes up to 4.
An origin of the ultrafine-grained fraction can be of two kinds: (a) breakage of initial grains into fragments with increased defect content and lattice distortion; (b) formation of finest nuclei of new grains by dynamic recrystallization.
When comparing textures of rods, subjected to different numbers of ECAP passes, one can see, that deformation processes develop non-monotonically.
According to obtained results, in the case of ECAP by route C the texture nonuniformity through rod's cross-section becomes more significant as the number of passes increases.
Emergence of the minor ultrafine-grained fraction results in scattering of the ECAP texture.

The original austenite grain boundary, discontinued , finer Lumpy, it is nearly continuous in the grain boundary of austenite.
In pearlite, it is slightly coarse than that in grain boundary.
Grain boundary of original austenite is almost continuous.
VN or VCN continues to precipitate within austenite crystal and number of grains increases: Precipitation at grain boundary, including grain boundary of original austenite, probably also including interface of ferrite or austenite.
In this case, when number of positions for harmonized heterogeneous nuclei will hardly change for ferrite within grain boundary of austenite, dimensions of ferrite grains will be slightly greater at grain boundary of isothermal ferrite austenite, as indicated in Fig 1.

The average grain size was determined from about 500 grains.
a 1 10 100 1000 10000 012345678 Particle diameter in µm Number of particles in 1/mm² 6060hom 6060hetr B 1 10 100 1000 012345678 Particle diameter in µm Number of particles in 1/mm² 6060hom 6060hetr Fig. 1 Cumulative two dimensional size distributions of large particles in the alloy.
The resulting grain sizes after annealing are shown in Fig. 4a.
The recrystallised grain size decreases with increasing strain.
The increase in recrystallised grain size at a strain of 5 to 10, as observed in Fig. 5, is probably related to a critical strain for grain-breaking, accompanied by a significant reduction in nucleation from old grain boundaries.

Materials and Methods Rice Grain Samples.
There are two groups of rice grain samples including four varieties of milled rice and one type of brown rice.
Acknowledgements This work is partially supported by Ministry of Higher Education Malaysia and Universiti Teknologi Malaysia under project number Q.J13000.7123.00H09.
Prediction of grain weight, brown rice weight and amylase content in single rice grains using near-infrared reflectance spectroscopy.
Kauffman, Chapter 6 : Grain Quality, Rice Improvement, P.

At R/2, the number of residual deformed grains increases significantly, and the deformation is elongated along the 45° direction.
With the increase in torsion amount, the recrystallization degree of the microstructure at the center of the sample gradually decreases, resulting in an increase in the number of residual deformed grains.
Blue represents recrystallized grains, yellow represents substructure grains, and red represents deformed grains.
It can be seen that not all small grains belong to recrystallized grains with low distortion energy.
Additionally, the deformation uniformity improves within and along the grain boundaries of large grains.

The model predictions were confirmed by the experimental measurements that a state of steady nanograin growth can be achieved by designing a certain solute concentration and a proper initial grain size. 1 Introduction Even though nanoscale grain sizes can be fairly easily achieved in many polycrystalline materials, nanostructure stability is a primary concern for subsequent processing and usage. [1, 2] Element doping is an effective way to enhance the microstructure stability of nanocrystalline alloys due to the role of solute segregation.[3] The theoretical predictions about effects of solute segregation [4, 5] have been confirmed by a number of alloys, such as Y-Fe [6], W-Ti [7] and Cu-Zr [8], the mean grain size of the stabilized structure decreases with increasing concentration of the solute element.
and are the corresponding grain interior variables.
is the specific solute excess at the grain boundary, which can be derived as , , and are the solute concentration, thickness and atomic density of the grain boundary.
∆G more negative) than those of other grain sizes.
The mean grain size of initial sample is 40.7 nm.

The largest grain size is less than 50μm and the smallest grain is about 10μm.
Small grain is the growing recrystalized grain, but the growing is not enough.
It also promotes the grain growth along different orientations because of the larger number of meta-crystal orientations in the shear zone.
Grain growth is due to the grain boundary migration process where the boundary of the growing grain migrate toward outside.
However, only the grain with highest grain boundary migration rate grows fast and the grain with slow grain boundary migration rate will be consumed.