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Grain size distribution in the sinter is an important index sign to measure the quality of sinter.
Calculation of Fractal Dimension for Grain Size Distribution Set the total weight of broken model invariant, each composition, will the part of the probability P which in the original grain (here, the probability P is connected with the broken body of their own strength and experimental condition) as the split ratio r to reduce the size, infinitely repeat, then generated a series of grain groups that was large and small, calculate the fractal dimension of grain group as follows, multiply the amount of re-construction the N grain is [2,3]:
The fractal dimension D [4] of grain group is:
Macroscopically, the sinter ore, which falls from a certain height and the lumpiness and the shapes difference, is combined with a number of different size massive sinter with the pore.
Therefore the fractal dimension D for grain size can be conveniently calculated by the Eq. 3.

This is because the existence of a sufficient number of isotropic crystal grains in the X-ray irradiation area are based on the X-ray diffraction theory.
From Eq.(1), if the stress plane condition in the sample surface is assumed, the stress components σ11P, σ22P and σ12P can be calculated and decided by the three numbers of ε33L values.
The average grain size is 2.23 mm.
Fig5(a) is for the crystal grain A and (b) is for the crystal grain B.
The blue marks are the results of the crystal grain A and red are of crystal grain B.

When adding 5wt% Mg, the mean grain size is the smallest, 0.712 mm, while the biggest grain size is 1.115mm in raw steel.
Table 2 Designed calcium and magnesium contents of experimental steel The number of the furnace 1 2 3 4 5 6 7 Ca (wt%) 0 1 3 5 0 0 0 Mg (wt%) 0 0 0 0 1 3 5 The steps of smelting the experimental steel are as follows
Then we measure the size of the grains in the figure and convert into the specific size of the grains.
The thick austenite grains have the heredity, that is to say, the thick austenite grains lead to the thick ferrite grains after the phase transformation.
When adding 5wt% Mg, the mean grain size is the smallest, 0.712 mm, while the biggest grain size is 1.115mm in raw steel.

The grain refinement is a constant process covering formation of low-angle grain boundaries, gradual increase in disorientation as an effect of dislocation accumulation and eventually formation of high-angle grain boundaries.
The microstructure remain grained with grain size on the same level (average grain diameter about 40 μm).
Grains size distribution for such case is shown in fig. 8.
After RCS processing number of low angle grain boundaries increased significantly.
Acknowledgment This work was supported by the European Union, Structural Funds Operational Program Innovative Economy - Project Number POIG 01.01.02-00-015/09 References [1] Yuntian T.

Introduction Severe plastic deformation breaks down the microstructure into finer and finer grains.
It is generally identified that the ultra-fine grained (UFG) structure exhibit a number of beneficial physical properties [4-7] (mechanical properties, elastic and damping properties, fatigue and creep, etc) in comparison to coarse grained crystals.
According to MiloŠ [8], the corrosion damage is more homogenous in the ultra-fine grained materials and the clear localized intergranular corrosion in coarse grained material.
The corrosion damage of UFG copper is macroscopically rather uniform whereas an obviously preferential grain boundary degradation and selective corrosion of some grain interiors was observed in CG copper.
The average grain size of Cu was refined to about 300 nm by ECAP for 12 passes.

The grains of Fe and S45C were significantly refined to the submicron size range using the HPT process, and the grain sizes were found to decrease with an increased number of turns (N).
In addition, the hardness of HPT-processed Fe was saturated with a further increase in the number of turns owing to the saturation of grain refinement.
A number of SPD processing techniques are now available.
The grain sizes were found to decrease with an increase in the number of turns (N).
The hardness of HPT-processed Fe was saturated with a further increase in the number of turns owing to the saturation of grain refinement.

Introduction Ultra-fine grained (UFG) metals and alloys with the grain size in the sub-micrometer range may exhibit a number of attractive properties, e.g. high strength and hardness, low-temperature superplastic behavior at high strain rates, improved magnetic properties [1], just to mention a few of them.
†Note that strictly speaking the recrystallization front is not a singular interface, but consists of a number of segments - individual grain boundaries - with own misorientation parameters.
While the C-type experiments do profit from an increased number of GBs that enhance the total GB flux and improvesthe counting statistic decisively, the B-type measurements are almost impossible due to contaminate grain growth.
Application of the back-pressure during ECAP processing (about 200 MPa) suppresses formation of the percolating porosity in Cu, if 4 passes are applied, and the percolating porosity appears again if the number of passes is increases to 8 or 12 [49]
Or they could be consumed by new grains due to recrystallization and grain growth.

Smaller sub-grains could be developed by further grain-coarsening (Fig. 1) in these grains by modifying the simulation.
The effects of the following parameters were investigated: ferrite/cementite interface free energies, temperature, carbon concentration, pearlite grain size number, pearlite interlamellar spacing.
Ever fewer nuclei of type 3 develop if the interface free energy decreases and at the end the number of type 3 nuclei will be lower than the number of type 1 nuclei.
An approximately linear curve is kept for the nucleation rate as a function of grain size number (Fig. 8).
Model of grain growth.

The steel structure consisted of large grains of high-temperature ferrite (~ 15%), without visible mesostructured, and martensite packages with a great number of low-angle boundaries.
The grain structure remained stable.
Relatively small number of carbides was detected at CSL special boundaries Σ11, Σ25b, Σ33с Σ41с.
In this case any high-angle boundaries can be considered as special ones, distinguished by the number of grain boundary defects.
Winning, Five-Parameter Grain Boundary Analysis by 3D EBSD of an Ultra Fine Grained CuZr Alloy Processed by Equal Channel Angular Pressing, Adv.

Severe plastic deformation techniques like equal channel angular pressing or accumulative roll bonding are used by number of researchers.
It is clear that the equiaxed α grains are surrounded by high angle grain boundaries (HAGBs).
When the smallest dimension of the grains becomes comparable to the size of grain boundary serration, DRX grains surrounded by high-angle boundaries is formed by the impingement of serrated initial grain boundaries in the geometrical DRX.
It is seen that θ particles exist on the grain boundaries of equiaxed α grains.
Meanwhile the final α grain size decreased.