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Residual strain is calculated as the original strain minus the strain eliminated by the number of recrystallizations, providing strain data for the next period.
As there are a large number of nodes on the workpiece, the section in the stable rolling stage is used as the main object and its calculated result is extracted.
As the workpiece has a large number of elements and nodes, we will use the slice from different parts at the stable rolling stage as our research object and extract its calculated result.
Fig.7 Austenitic Grain Size Changes at Edge Fig.8 Austenitic Grain Size Changes at 1/4 Width Figure 8 shows the Austenitic grain size change at 1/4 from the surface.
Recrystallization and grain growth in hot rolling.

At 623 K or higher, however, adhering to the roll became conspicuous, workability declined considerably, and the crystal grains were greatly coarsened.
Accordingly, it was found that the shear bands gradually became wider with increasing the number of passes, and the average diameter of the crystal grain became smaller gradually.
The problems with sheets processed by DSR with unidirectional shear, as mentioned above, are the considerable inhomogeneity in grain size and texture between the shear bands and other areas, and the impossibility of increasing the number of passes because cracks readily occurred in the shear bands.
Changes of tensile properties with number of DSR-passes Table 2.
The change of formability with the number of DSR passes

SEM micrographs were used to study the morphology and grain growth.
Morphology, size and grain boundaries changed in each composition.
Basically it is the number of ferrous ions on octahedral sites that play a dominant role in these properties.
According to Maxwell-Wagner model, ferrite materials consist of well conducting grains separated by poorly conducting grain boundaries [18].
At lower frequency grain boundaries were more effective in terms of conductivity and permittivity than grains, so ( ε ) was high and it decreased as applied frequency increased.

Reciprocative sliding wear behaviour of a number of WC-Co based hardmetal grades was investigated using a small-scale pin-on-plate tribometer.
The WC10Co(Cr/V) grade displays the finest WC grain structure, with 50 % of the grains being smaller than 0.3 µm and 95 % smaller than 0.7 µm.
The generator settings for a number of EDM regimes is given elsewhere [5].
SEM investigation of the wear scars revealed that wear behavior of the cemented carbides is mainly controlled by abrasion, grain cracking, grain fracture and grain removal, Fig. 2.
Reducing WC grain size and/or increasing hardness were noticed to considerably enhance the wear resistance.

The results show that microstructure of sintered materials consists of spherical grains with approximate size of 100 nm.
The microstructure of sintered materials that consists of equiaxed grains seems not to be influenced by α-Si3N4 in starting powders.
The α-Si3N4, Si2N2O and β-Si3N4 phase can not be distinguished because the difference in mean atomic number is too small.
Crack growth values versus numbers of thermal shock for Si3N4 nano-ceramic composites samples at different temperature difference (a) sample A, (b) sample B, (c) sample C, (d) sample D Figure 4 shows the relationship of the crack growth values and temperature difference when cycle number is 70.
The main results are as follows: (1) The microstructure of Si3N4 nano–ceramics consists of spherical grains and the addition of α-Si3N4 to starting powders has no effect on the grain morphology of sintered materials.

For example, for SMC (α + β) titanium alloys superplastic flow is observed already at 873–973 K [1–2], whereas for fine-grained (grain size 2–10 µm) alloys it is observed at temperatures above 1100 K [3].
The sample consisted of at least 200 grains.
The contribution of grain boundary sliding (GBS) to the total deformation was calculated from the formula [6]: , (1) where h is the average stair height, n is the number of boundaries per unit length on which stairs were observed, and k = 1.5 is constant.
This will result in cracking along the grain boundaries.
Raj, Grain size distribution effects in superplasticity, Acta Metall. 29 (1981) 607–616

Results and Discussion In order to investigate grain orientation, grain size and grain morphology of the T4P state alloy sheet under various solution treatment tempers, EBSD technique is used in this study.
Fig. 1 shows that the microstructure of 6A16 aluminum alloy cold-rolled sheet is lath-shaped, and there is a large number of subcrystals with small size inside the lath-shaped grains.
The grain size is not uniform, and the size is larger.
(a) (b) Fig. 1 EBSD maps of the cold-rolled alloy sheets: (a) grain microstructure, (b) grain size distribution.
(b) (a) (d) (c) (f) (e) (h) (g) (j) (i) Fig. 2 EBSD maps of the T4P treated alloy sheets: (a) grain microstructure of sheet A, (b) grain size distribution of sheet A, (c) grain microstructure of sheet B, (d) grain size distribution of sheet B, (e) grain microstructure of sheet C, (f) grain size distribution of sheet C, (g) grain microstructure of sheet D, (h) grain size distribution of sheet D, (i) grain microstructure of sheet E and (j) grain size distribution of sheet E.

Austenitic grain size and morphology are the most important factors on tensile property.
They have the significant difference of γ grain size and morphologies.
The rapid cooling speed caused the precipitation of Cr2N in the ferrite grain or among grain boundaries.
When the temperature is of 1250 (Fig. 6d), the number of the tensile fracture dimples decreases significantly and the area of stripped separation surface increases (arrow D marked in the Fig.6d).
Austenite grain size and morphology are main factors affecting the tensile strength.

The microstructure of sintered materials consists of spherical grains and the addition of α–Si3N4 to starting powders does not affect the grain morphology.
Grain morphology and size evidence that it is impossible to obtain high density with avoiding grain growth which occurs simultaneously with the disappearance of the amorphous phase.
Grain coarsening and morphology evolution during sintering are multi-stage processes: (i) particle rearrangement aided by the lubricant action of the liquid, (ii) dissolution and crystallization of very fine grains, (iii) dissolution and recrystallization of coarser grains.
Effect of grain size on mechanical properties is complicated.
The strength and toughness usually increase with the decrease in grain size, while too fine grains have an opposite effect.

Figure 1 Grain Size Distribution Curves for Yi-river Bed Sediments and Weathered Soils The grain size test, the compaction test and the field density test were performed for the variation factors of each material such as bed sediments, granitic weathered soils and mixing soils.In this test, a 10 ton-vibration compaction roller was used, and the field density was measured through the field density test based on the sand replacement method .
However, there was almost no change of dry density by the number of round compactions (Refer to Figure 2(b)).
The Grain Size Distribution Curves based on the mixing ratio of Yi-river Bed Sediment mixing through the Laboratory Test (2) Field Mixing Characteristic To propose a field mixing method for Yi-river bed sediments (SP) and the granitic weathered soil using the back hoe machine(0.6m3) the grain size distribution curve was compared with the grain size distribution curve based on the number of mixings for the bed sediment-mixed with the mixed volume of 12m3 for each element.
As shown in Figure 4, mixing soil of the grain size distribution curves according to the number of field mixings against 12m3 of bed sediment-mixed soils, the grain size distribution characteristic after 5-time mixing showed the similarity with the laboratory test result.Considering the field conditions, it is recommended to mix 10 times or more.
It shows that a mixing with fine soils improves the compaction characteristic.(2) With respect to the number of field mixing with 12m3 of bed sediment-mixed soils, the grain size distribution characteristic of the Yi-river bed sediments after 5-time mixing using the back hoe was similar with the laboratory test result.