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In contrast, in the samples with high ductility, larger NbC precipitates with lower number densities are observed.
BN precipitates develop number densities of approx. 1012 m-3.
Also, the relatively small number density of 1014 particles per m3 gives a number of 10-4 particles per µm3, which strongly decreases the chance of detecting any such precipitates in TEM.
Finally, AlN tends to precipitate on austenite grain boundaries.
Grant Agreement number: RFSR-CT-2011-00008.

Recovery and recrystallization as a function of deformed microstructure orientation in coarse grained cold-rolled Ni H.S.
Samples with an initial average grain size of approx. 500µm were deformed to strains of up to εvM = 4.5.
Twinning was observed also to play an important role in the generation of recrystallized grains, with twin chains of up to 3 generations being observed.
Experimental Methods The starting material was a 6 mm plate of Ni (99.96%) with an average grain size of d = 500 µm, corresponding to an average of 12 grains across the sample thickness.
Acknowledgements This work was supported by the National Natural Science Foundation of China under contract numbers 50371041 and 50231030.

Because Bi is brittle phase and distributed in the copper alloy matrix grain boundaries as thin ribbon network.
With the increasing of the content of Bi, a large number of Bi gathers in copper grain boundaries and begins to join together to form a status like a continuous chip mesh belt, as what shown in the metallographic diagrams 5# and 7# of copper-bismuth bearing material in Figure 1.
Due to without brittle Bi phase, the number of crack source in the organization of material is few, and the copper alloy matrix which has good toughness in the process of impact fracture has strong shears deformation, microvoids form in the local region, begin to grow and gather.
The SEM photographs of fracture show that there is cracks which grow to depth along the grain boundaries.
The strong Bi energy peak occurs at the fracture grain boundaries, which proves that the crack generation,growth,until fracture occur along the grain boundaries of Bi-rich phase.

It is observed that this ratio does not change with the austenite grain size and bainite forming temperature.
The bainite has been reported to nucleate at the grain boundaries of prior austenite [1].
The nucleation of bainite on the austenite grain boundaries has been studied for decades and the influence of austenite grain boundary features on the variant selection of bainite was discussed recently in details [2].
Results and Discussion Grain size after austenitization at different temperatures.
Heat treatment Type I Type II Type III Number Ratio, % Number Ratio, % Number Ratio, % 1 1050×15min→680C×1hr→340C×1hr 80 81.6 7 7.2 11 11.2 2 1050×15min→680C×1hr→500C×1hr 77 81.9 8 8.5 9 9.6 3 1250×15min→680C×1hr→340C×30m 82 82.0 8 8.0 10 10.0 4 1250×15min→680C×1hr→500C×30m 84 80.0 9 8.6 12 11.4 The austenitization temperature is changed to obtain different grain size.

For this, the grains formed during DRX were identified by their appearance in EBSD orientation maps and the orientations of these grains determined.
The twin boundaries only reveal however twinning in partly twinned grains - some grains are in fact fully re-oriented by twinning.
A qualitative estimation of the extent of slip activity can be made by looking at the number of low angle (between 2° and 4°) misorientations within each grain.
For the ND sample at high strains many DRX grains are formed along the parent grain boundaries (Fig. 4c).
In the ND sample the DRX grains have the same orientations as the grains deforming by slip.

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].

During the process of grain growth, there are both grain boundary diffusion and grain boundary migration.
Only those grains with the size of YSZ nuclei d≥dc will grow in the later grain growth steps.
Therefore it is necessary to hold a period of time (e.g. 2h) at about 1000°C, which helps to form a large number of nuclei with size larger than dc [18,19].
The grain growth is associated with grain boundary motion, which is mainly controlled by grain boundary migration in higher energy state.
As we know, the grain growth behavior contains two processes: grain boundary diffusion and grain boundary migration.

Formation of a multiphase state, represented by grains of α-iron and inclusions of carbide phases based on iron, chromium, and niobium, is revealed.
The total number of counterbody rotations was 5000.
Namely, mass formation of nanoscale particles of carbide phases located in the volume and along boundaries of α-iron grains.
Formation of a multiphase state, represented by grains of α-iron and inclusions of carbide phases based on iron, chromium, and niobium, is revealed.
It is shown that the main carbide phase is the iron-based carbide, located in the form of extended layers separating grains of α-iron.

Only a limited number of probes is available to determine the how the material behaves under these dynamic loads.
The microstructure did not have a significant texture, and the departures from perfectly random orientation can be attributed to the statistics resulting from a fairly small number (a few tens) of larger grains.
The grains are largely free of dislocations and other defects, apart from the grain boundaries.
Like any rigid body rotation, the lattice orientation is specified by three numbers, often expressed in terms of Euler angles [55].
The number 8 is chosen to equal the number of nearest neighbors in the strain-free perfect bcc lattice, and this number would be different in different lattices.

Quite a number of models have been developed over several decades ago, involving particle rearrangement and grain growth during sintering, such as monte carlo, molecular dynamic, finite element analysis, discrete element method, field variable model and the combination of them.
and the coefficients for volume and grain boundary diffusion, respectively, and the width of grain boundary.
An alternative method is to estimate the apparent sintering activation energy on the basis of the MSC itself through determining the minimum of the mean residual squares (sum of residual squares divided by total number of data points).
The model indicates that a powder with discrete particles below 50nm is needed to produce an average grain size of less than 100nm.
In the grain growth behavior research, the MSC equations are also further modified to include the effect of the solid volume fraction on the grain growth constant.