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By using this method, a 2-D microstructure can be modeled considering grain orientations as well as individual anisotropic elastic properties in each grain.
Fig. 1 shows the development of surface roughness with increasing number of loading cycles.
Based on EBSD data the grain boundary of each grain is meshed with boundary elements and specific elastic anisotropic properties are considered in each grain depending on the crystallographic orientation.
The phase map in Fig. 7c shows also the expansion of the martensitic phase in grain 1 (in addition to grain 3).
Due to gradual increase of simulated plastic deformation in shear bands the number and size of generated martensite embryos are growing with increasing number of simulated loading cycles.

The initial grain size was about 80µm.
It is shown that the number of dynamic recrystallization grains is less at lower temperature and higher strain rate than higher temperature and lower strain rate.
In general, new boundaries were formed in slip bands both near original grain boundaries and within original grains.
Fig.4 TEM images of dislocation features at 0.001s -1 and (a) 623K in twinning (b) 623K in DRX grains (c) 673K in grain-boundaries Conclusions 1.
The number of dynamic recrystallization grains is less at lower temperature and higher strain rate than higher temperature and lower strain rate.

Prior austenite grain size.
It can be seen that the grain is anisometric and fine.
The results are shown in Table 3 and Fig. 2c.The grain size is mainly concentrated below 18μm.When the quenching temperature increases by 10℃,the number of grain with size between 6μm and 12μmdecreases from 3928 to 3325,and the number of grain with size between 12μm and 18μmincreases from 1277 to 1459, but the average grain size is almost unchanged.
Fig.1Mechanical properties after different heat treatment: (a) rockwell hardness; (b) tensile strength and yield strength; (c) impact toughness Table 3 Results for prior austenite grain size measurement Quenching temperature minimum grain diameter maximum grain diameter Average grain diameter 910 1.09 39.05 8.01 920 1.18 47.06 8.31 Fig.2(a) OM image of prior austenite grain size quenching at 910℃；(b) OM image of prior austenite grain size quenching at 920℃；(c)Statistical results for grain size quenching at 910℃ and 920℃;(d) OM image of microstructure for process2-3.
Fig.3(a) TEM image of martensite lath for process number 1;(b) TEM image of martensite lath for process number 2-1;(c) TEM image of martensite lath for process number 2-2;(c) TEM image of martensite lath for process number 2-3 Analysis of carbides.

The acicular ferrite grains formed in the austenite grains were trigged by the intragranular ferrite grain(s) formed around TiN.
The pole figure from the ferrite grain and the particle in Fig. 3(a) show that the (001) plane of a ferrite grain is parallel to the (001) plane of a TiN, and the (011) plane of a ferrite grain is parallel to the (001) plane of a TiN.
Fig. 4 shows an inclusion surrounded by a number of ferrite grains corresponding to Fig. 2(a).
The acicular ferrite grains formed in the austenite grains were trigged by the ferrite grains formed around TiN.
The acicular ferrite grains formed in the austenite grains were trigged by the intragranular ferrite grain(s) formed around TiN.

Thus magnetic electrodepositing which has the advantage of less polluting as a new electroforming process comes into being[6].And numbers of research scholars have paid a great deal of attention to it[7-9].
And the grain nucleation rate is less than the growth rate.
So the grain of the nickel electroforming layer is refined.
As the magnetic intensity increases to 0.6T, the circular grains of the surface are evenly distributed, with the average grain size of 0.89μm.
With the increase of magnetic field intensity, a large number of nano particles can be uniformly deposited on the casting layer to improve the nucleation rate, in the function of grain refinement.

The maximum likely holding depth (number of pieces in process at once) has to be anticipated in the layout and in the table drive zoning.
Generating strength through grain refinement relies on sufficiency of strain, and since the grain size in a transformed phase is strongly dependent on the grain size of its precursor, sufficiency of austenite strain is a prerequisite for a fine-grained final product.
The plate mill variant is only just appearing, for a number of reasons.
With a number of collected data the neural network can be retrained and thus improved even more in precision.
There are a number of aspects to achieving the correct microstructure, which combine to define the processing path required for a product.

Hence, virtually all positrons thermalized inside grains diffuse to grain interfaces and are trapped at open volume defects there.
Because of smaller size of Cr atoms, the lifetime of trapped positron increases with increasing number of Cr neighbors surrounding the trap.
Hence, Cr cations scavenging electrons should be located at grain boundaries.
This appears due to Cr cations segregated at grain boundaries.
Bečvář: Application of Maximum-Likelihood Method to Decomposition of Positron-Lifetime Spectra to Finite Number of Components, Mater.

The size of t he grains varies from 220μm to 50μm and the average size is measured to be 170μm.
A crack along the grain boundary is also found in the fracture surface.
Although there are many submicroscopic particles of insoluble solid impurities in the melt, the number of active particles is insufficient for effective heterogeneous nucleation.
Meanwhile, a large number of solid impurity particles, such as the Mn-based inter-metallic compounds, are universally distributed in the AZ91D alloy melt.
These changes were consistent with the fine uniform dendrite grains.

EBSD mapping shows that the 'new' grains appear first on the boundaries of deformed {111} grains and have high angle misorientations with the deformed grains, although the new grains are also of {111} type. {111} type deformed grains are recrystallised first due to their higher stored energy relative to {001} grains.
The as deformed microstructure is characterised by elongated grains of the {001} and {111} type (Fig 3a), the {111} grains show a large number of subgrain boundaries with the subgrains being generally quite small, <5µm in diameter.
They mostly occur on grain boundaries between the {111} grains and the {001} grains, and as they grow they consume the {111} grains.
However we can say that: • {111} grains with HAGBs nucleate on the grain boundaries of deformed {111} grains
• {001} grains remain for longer during the anneal than {111} grains because of their relatively low stored energy. • {001} grains tend to be consumed by new {111} grains rather than nucleate new {001} grains

The σr max value decreases noticeably with the increasing number of thermomechanical cycles, then this reduction slows down, and stabilizes after reaching N=30 cycles..
Thus, the grain size decreases from 5-10 microns down to 35 nm (Table 1).
The effect of the number of ECAP passes (N) at 450oC for Ti-50.2%Ni alloy and PDA temperature for Ti-50.6%Ni alloy on characteristic temperatures is shown in Fig. 2a,b.
Characteristic temperature dependences as a function of number of ECAP passes (at 450°С) for alloy 2 (a) and as a function of the annealing temperature for alloy 3 (b).
Ultrafine Grained Materials IV.