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Depth of cut was 1 μm and the truing pass number was 500.
Truer materials Contact area Mo, Ta, Nb, W, GC, SUS304, S50C 3 mm × 3 mm Wheel Grain size Shape Rotational speed Resinoid bonded diamond SD400, SD1200,SD2000 Φ10 × 20 mm 1000 min-1 Depth of cut 1 μm/pass Truing pass number 500 pass Feed 30 mm/min Coolant Solution type Fig. 6.
Radial position mm Depth μm 0.08 μm Rz 0.014μm Ra Fig. 11 shows a surface roughness change using each grain size of the wheel.
In the center area, surface roughness is better in each grain size of the wheel.
As an abrasive, diamond slurry of 0 - 1 µm in grain size and 1 wt% was used.

For Ti micro-alloyed steels, refine grain strengthening and precipitation strengthening are the most important strengthening methods.
Solid precipitated TiN in the slab will restrain the growth of re-crystallized grains in rolling, while the TiC has little effect on the growth of re-crystallized grains due to its larger size.
From Figure 7-c it can be seen that a large number of nano-sized precipitates are distributed along the dislocation line, some dislocations even form dislocation ring.
The experimental steel has a large number of nano-sized precipitates, and it has a high dislocation density.
Solid precipitate TiN in the slabs will restrain the growth of recrystalized grains in rolling, while TiC has less effect on the growth of recrystalized grains due to its larger size.

Variant selection rule of plate martensite in a coarse-grained Fe-28.5at.
Prior austenite grain boundaries were hard to recognize.
The bold line in Fig. 2 indicates prior austenite grain boundaries.
Figure 2 shows that the martensite plates mutually aligned in the prior austenite grain.
Since the number of analyzed examples is still limited, additional investigations should be carried out.

(a) tensile properties of the rolling direction (L), (b) tensile properties of the thickness direction (ST) and (c) fracture toughness Grain structure The grain structure of the alloys with different pre-deformation degrees is characterized by EBSD maps and the results are shown in Fig. 2.
All the alloys are composed of pan-caked grains and a few recrystallized grains, which is mainly attributed to the recrystallization of the rolled plates during the solution treatment.
Since the aging temperature of 145℃ is far from sufficient to generate apparent changes in grain structure, the grain morphology change can be attributed to the slip deformation in the pre-deformation [15].
Compared with the SADPs of the alloys with pre-deformation, it can be found that the short diagonal of the diamond of the alloy without pre-deformation is more pronounced, indicating a higher number of θ' phases, while the brightness of the diffraction spots of the T1 phase is significantly weaker, indicating a lower number of T1 phases.
Moreover, T1 phases tend to precipitate near the grain boundaries while there are few T1 phases in the alloy grains without pre-deformation.

The contrast in the BSE image is caused by the different grain orientations; a large number of twin boundaries can be seen.
Figure 3 shows EBSP grain-boundary misorientation distribution.
In the present 36%Ni steel, the initial grain size was 10 µm.
Such a process is called "grain subdivision" [9].
The mechanism of ultrafine grain formation can be understood based on a grain subdivision process. 2.

The experimental results showed that in the composites reinforced with hybrid SiC particles after cold isostatic pressing treatment, the agglomeration phenomenon and overlap phenomenon around the micron SiC particles disappeared and the surrounding defects were obviously improved, the grains were flattened, and the material was more densely.
After the composite material is treated by cold isostatic pressing, the composite material undergoes significant plastic flow due to external pressure, and voids and loose areas existing inside the composite material matrix are reduced, and the internal grain of the material is also reduced.
The joint between the crystal grains is even closer.
After cold isostatic pressing, the agglomeration and overlap of the micron SiC particles disappeared, and due to the external pressure, the matrix is plastically deformed, and the defects around it are obviously improved, the grains are flattened and the material is more compact. 2.
Acknowledgments This work was financially supported by the Natural Science Foundation of China (grant number 51501167), and Henan Province Science and Technology Research Project (grant number 162102210064).

The results show that the microstructure is ferrite with the grain size of grade 11 and quantities of linear MnS inclusions, grainy manganese-niobium composite oxides and small NbC precipitates are formed in the steel.
The average value of hydrogen permeation resistance of the steel is 33 min·mm-2, the enameling adherence is evaluated as level A1and the number of the pin-hole defects in the enameled steel is less than 10 per square meter.
The microstructure is ferrite with the grain size of grade 11.
The number of the pin-hole defects is no more than 10 per square meter, which indicates that the pin-hole resistance of the steel is fine.
In this research, a large number of linear MnS inclusions, grainy composite oxides and fine NbC precipitates are formed in the steel by the chemical composition design and technology control.

New grains are only formed in the MSB areas.
(e) misorientation profile across grain (parallel to ND).
Nucleation of new grains and growth process.
The occurrence of the cube oriented grains.
Once formed the new grains exhibit a strong tendency to grow by forming new grain boundaries through recrystallization twinning and hence change their orientation.

On the other hand, the extrinsic CMR effect [11], which frequently related to the natural of grain boundaries, is directly influence by the microstructure formation of the grain.
From Fig. 3, samples show porous microstructure with small grain size.
The increase in sintering temperature promoted grain growth and microstructure densification which yield the grains size to increase [15].
Area of selection is based on different grain contrast, shape or size.
In fact, different contrast appears due to different density of state as each element having its own atomic number.

However, with high amounts of Nb, abnormal grain growth and precipitation can occur, especially in coarse grain heat affected zone (CGHAZ), which can deteriorate the impact toughness [6].
Wu et al. [9] showed that Mo addition can increase the number density of precipitates and also diminished the size of these precipitates, which promoted the refinement of the grain size and the enhancement of the steel toughness in Nb-Mo steel.
The purpose was to simulate the coarse-grained zone of HAZ region (CGHAZ) and partially re-austenitised inter-critical zone (ICHAZ).
Measuring point 1 was located on the ICHAZ region, points 2–4 on the fine grained HAZ (FGHAZ) and 4–12 on the coarse grained HAZ (CGHAZ).
Shorter t8/5 time (5 s) produced generally better impact toughness properties compared to longer t8/5 time (15 s), which can be consequence of smaller grain size.