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The grain size of α phase was about 200 µm.
Raising the temperature to 720 °C resulted in an increase of the number of rotations that load to the destruction of the sample (from 7 for 700 °C to 16 for 720 °C).
The grain size at the surface was about 10 μm, it was about 60 μm in the centre, the fine grained surface layer was about 2.4 mm thick.
It should be noted that, elongated grains of the α phase, together with small grains of the same phase of a globular shape of 5 μm size were also observed.
The α grains are colored in grey, σ phase grains in white.

After ultra fast reheating with average reheating rates of 1000°C/s and higher a significant grain refinement was observed with an average ferrite grain size of ~1µm.
The obtained final ferrite grain size depends significantly on both the reheating temperature and the reheating rate.
However, the number of studies concerning the recrystallization and transformation behaviour in the conditions of fast reheating of cold rolled steel sheets with heating rates higher than 100°C/s is limited [5,6].
The grain size of ~1 µm is obtained in ultrafast reheated samples in the temperature interval 760-930°C but the question for grain growth in isothermal conditions after ultrafast reheating still remains to be investigated.
“Grain Refinement of a Cold Rolled TRIP Assisted Steel after Ultra Short Annealing” In proc of Rex&GG- IV Sheffield 2010, in print.

Grain fragmentation was allowed by fixing for each grain a first neighbor co-spinning grain and another identically oriented neighbor attached to a different co-spinning grain (Fig. 1).
Spatial distribution of crystals and fragments Nucleation: Nucleation will happen in grains with stored energies larger than certain threshold )]min(E)[max(Ep)min(EU i i i − += (1) with a probability given by:    ≥≥≥≥ −−−− <<<< ==== UE if A/E UE if 0 pr i 2 i i i )exp( (2) where Ei is the deformation energy of the grain i measured as a function of the CRSS, p is a number selected between 0 and 1 representing the nucleation threshold and A is a constant.
The N grains are examined by pairs to check the probability of each pair of collapsing, by one grain growing into the other, in just one grain.
If the probability given by Eq. 3 is larger than a randomly generated number between 0 and 1 we apply Eq. 7.
No grain will grow at expenses of already recrystallized grains [6].

The polishing wear of the diamond grain is showed in Fig.3.
Fig.2 Diamond grain with whole crystalline form Fig.3 The polished diamond grain Partial breakage is showed in Fig.4.
The whole breakage will take place when the cutting force acting on one diamond grain surpasses the pressure strength of diamond grain.
The sharpness of the saw would decline with the polished grain number increasing and the saw appeared low cutting ability
(4) Partial fall off is that the diamond grains broken fall off from the nickel-plate layer because the bonding force is not enough to hold grain onto the nickel layer.

The fraction number of high angular boundaries (HAB) is 23%.
The number of HAB is 60%.
However, the low fraction of HAB and high number of coarse grains has being indicated that recrystallization processes is not fully completed in the structure.
The discrepancies of average grain size number in considered rolling by shape mill were Dd =0.1, Dd=0.04 and Dd=0.02 after last rolling stage.
These processes had equilibrium at the number of HAB about 60%.

Some cladding tubes were annealed at 700oC for 3 hrs to induce the grain growth.
In the annealed Zr-Nb-Sn-Fe alloy cladding tubes, dislocation-free recrystallized grains with a larger grain size were observed.
However, other studies have indicated that the creep rate may increase or decrease with decreasing grain size, or be grain size-insensitive in copper6.
Both models suggest that the effect of grain size varies with experimental temperature and conditions even in identical materials and the dislocation activity near-grain-boundary regions could increase the creep rate in the small grain size region, supporting the decrease of creep rate with increase of grain size in the present study.
In general, with the increase of temperature, the number and mobility of thermal vacancies increase, causing more vacancies or impurities to diffuse to grain boundaries.

High grain density of diamond tool can be obtained.
The MBD type diamond grains were grit size of 140/170.
Diamond grain numbers per unit area were computed as grain density.
During grinding processes, grains could not be easily pulled out and high grain density of diamond tool was keeping.
During the buildup operations, ultrasonic agitation can compact grains and guarantee the nice contact between substrate and grains.

Alloy properties after aging treatment were related to the number of θ’ and θ” phases.
With the increase of addition amounts, a large number of Al3Zr or Al3Y particles generated that increased resistance to dislocation motion.
It can be seen from Fig. 12(a) that the particles with large size and a certain number of dimples appear on whole surface morphology of the as-cast Y-containing alloy.
After T6 heat treatment, not only the number and size of cavities and cracks are greatly reduced, but also the structures of tear ridges and a certain number of dimples emerged, which are small and distribute uniformly, and the proportion of alloy ductile fracture increases.
Further discovery through contrasting with alloys added additions of Y and (Zr+Y) was that there existed changes of grain size and number and shape of θ phase, which was an important factor of alloy properties change.

After solution treatment, the distribution of second phase decreased and after aging, there are many second phases precipitated along the grain boundary and inside the grains.
After aging, there are many second phases precipitated along the grain boundary and inside the grains and the aging microstructure are relatively uniform.
In the early stage of immersion, large numbers of hydrogen bubbles are evidently observed arising from the surface of as-cast specimens, indicating a fast rate of hydrogen evolution due to the reaction of Mg matrix with the corrosive electrolyte, while the numbers of hydrogen bubbles arising from the surfaces of the solution treatment and aging are comparatively fewer.
The second phase is expected to act as a barrier when there is a small grain size.
And after aging, there are many second phases precipitated along the grain boundary and inside the grains and the aging microstructure are relatively uniform.

The average grain diameter and standard deviation values obtained by counting for a number of crystal grains, with constant thickness, was also evaluated from TEM analysis.
The smaller and more uniform is grain size, the higher is Hc, and the lower is Ms.
Such extremely small grains may cause super-paramagnetic behavior of the film.
The constant C denotes the total number of atoms per unit volume.
The structure was designed to obtain a fine grain size of the magnetic layer.