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The 300-500 nm grain size has been reached (see Fig. 7).
As a result of TE, the grain refinement to submicron level has occurred (see Fig. 8).
This fact allows us to increase considerably the number of patients which can be operated in order to insert such implants.
Zhu: Producing Bulk Ultrafine-Grained Materials by Severe Plastic Deformation.
Symp. on Ultrafine Grained Materials, eds.

Repeated quenching is used as a grain refinement method.
Repeated quenching is used as a grain refinement method.
The number of measurements was three times for each.
The total number of cycles was 1.0×108.
The horizontal axis shows the total number of cycles to failure.

The concentration of the grain boundary corresponds to the number of atoms existing on the grain surfaces with a diameter of 16 μm, which is slightly larger than the block boundary of F82H [18].
The defect is related to grain boundaries.
Acknowledgement This work was supported by JSPS KAKENHI Grant Number JP18K03584.
Henderson Brown, Dislocations in grain boundaries and grain boundary sliding, Acta Metall. 15 (1967) 857–860
McLean, Changes produced by deformation in grains and grain boundaries of nickel, Met.

Micrographs of the particle distribution on surface of micro grinding tools Through the investigation and dimension measurement to different size of micro grinding tool, the distribution of CBN grains on the surface of the substrate could be accomplished and it could be described by G0 which stands for number of grains within 1 mm2 of square on surface of the substrate.
Fig. 6 shows the surface of work piece in micro grinding view by microscope, tool is 500 μm diameter, Fig. 6(a) is F800# grain particle size, Fig. 6(b) is F1200# grain particle size, Fig. 6(c) is F3000# grain particle size.
Fig. 7(a) is F800# grain particle size, measure range is 60 μm×60 μm.
Fig. 7(b) is F3000# grain particle size, measure range is 30 μm×30 μm.
From the result it is concluded that large number of grains could turn to low Ra, the F3000# particle size reach a roughness of 0.086 μm.

From a large number electoral ward electron diffraction (SAD) analysis, BNf’s crystal structure have close relation with crystalline grain size, crystalline grain size has close relation with technology condition.
BNf’s crystalline grain size and layer interval d002 value change following a certain rule (From table 2) which is crystalline grain turning large ,d002 value turning gradually small.
In BNf, crystalline grain grows up at different level.
Crystal grain is small and even, arranging closely, only small air holes exist.
Surface crystalline grain appears long state and arranges by axle.

Fig. 2 Schematic explanation of the experimental and measurements set up for mirror-like finishing process Grain on the lapping head X Z Y Lens Lens Lapping head Vibration sensor Work piece Spindle rotation Slurry supply Lapping pressure FFT Vibration analyser Lapping tool Table. 1 Conditions of lapping for mirror-like surface finishing process Lapping slurry Water : PEO = 98:2 wt. % Diamond grain size #400~500 48.8[µm] #1200 15.8[µm] #2500 11.0[µm] Number of active grain on lapping head 30 230 850 Lapping speed 3000, 4000 [mm/min] (optimum) Lapping pressure 30 [MPa] , 40 [MPa], 45 [MPa] (optimum) Lapping time (Total) 15 [min] (optimum) Lapping head material Polypropylene (HV 11) Work piece material Brass (HV 91) , S45C (HV 170) , V10 (HV 2200) Type of lathe Linear motor lathe Influencing factors such as grain characteristics, lapping head hardness, lapping pressure, lapping speed, residual stress
Effect of active grain characteristics on lapping process.
The possibility of grain drop out is higher than other grain size of #400~500 and #1200 in this process.
However, there is limitation of lapping speed to maintain the number of active grain on the head to perform two body abrasive machining that has higher material removal rate than three body abrasive machining.
The number of active grains on the head influences on uniform improvement of surface roughness and geometrical form simultaneously.

The three IF steels are numbered 1#, 2#, and 3# in order of finishing rolling temperature from high to low.
The grain size of 3# is relatively small, with an average grain diameter of 35 μm, and the grain size is elongated along the rolling direction.
After annealing, the number of red and green grains decreased, while the number of blue grains increased significantly, indicating that γ-fiber formed strongly after annealing, with weak α-fiber and {110} texture.
Fig. 4 The proportion of blue grain area.
Therefore, {100}-oriented recrystallized grains are very few, and {111}-oriented grains dominate in the recrystallized grains [9, 10].

This feature made a number of researchers study experimentally the transformations in Fe–9 %Cr alloys [2–6].
Legend numbers indicate transformation temperatures (in deg Celcius).
The fact that nucleation energy for austenite ® ferrite transformation is small compared to the activation energy of growth also found its confirmation in direct synchrotron radiation measurements of the number of ferrite grains during transformation [10].
Acknowledgements The work was financially supported by the Ministry of Education and Science of the Russian Federation (state assignment No. 3.9660.2017/BCh; publication number 3.9660.2017/8.9).
Cahn, The kinetics of grain boundary nucleated reactions, Acta Metallurgica, 4 (1956) 449-459

a b Fig. 2 shows equiaxed grains in TP-100-1 and TP-325-1 extrudates after extrusion and 825 o C anneal for 30 minutes.
The grain size was similar to the starting powders, (Fig. 1 and Fig. 2).
There was also subgrain structure within the extrudates that consisted of a needle phase within grains and an intergranular phase, Fig. 3.
Contrast due to low atomic number elements was detected within the needles and at intergranular locations that could not be explained by oxygen, nitrogen or boron levels greater than those in the matrix, Fig. 3.
Backscatter electron micrograph of TP-325-1 extrudate after annealing at 825 o C for 30 minutes showing low atomic number element contrast from needles and intergranular particles.

To find main cause of increasing of void volume fraction, the increasing number of voids was classified by size.
When strain level is 10% for fracture, micro void nucleated mainly at ferrite-martensite grain boundary and in ferrite grain concerning both materials.
(a) Material A (b) Material B Fig. 7 Micro void number classified by size in each material.
Fig. 8 Micro void number classified by nucleation site in each deformation stage.
This is caused that micro void nucleates not only grain boundary but in the main grain.