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The hot-rolling test was carried on the hot tandem mill, final rolled in austenite, and the hot rolled thickness was 4.0mm.the hot-rolling take normal heating system, the coiling temperature were separately are 710℃and 670℃, the serial number respectively was A# and B#，and its chemical composition shown in table 1.
All of the experimental steels are perfect recrystallization, and their grain sizes are almost equiaxial under higher 75% to 85% cold reduction ratio, and the grain about 7.0 to 11.0 grade.
But the separation rolls grain growth's nail to be small in the recrystallization process.
These grains growing firstly devour the matrix of the γ texture orientation.
The recrystallization makes the new grains be nucleation and grain growth, so the textures change significantly[3].

The average grain size is about 20μm.
In the primary stage of short fatigue cracks, the fractal dimension increases rapidly with the increasing number of cycles, which is approximately linear.
The free surface effect is taken into account, i.e. grains of material surface constrained by the surrounding grains weaker than the internals, making the grains of material surface still have plastic strain concentration at a lower stress level, so that short cracks formed where there is a higher growth rate.
The fractal curves under various nominal strain amplitudes with the number of cycles are put into the same coordinate system, where the abscissa denotes the percentage of the material fatigue life (N/Nf) instead of the number of cycles N, as shown in Fig. 5.
As the increasing of the cyclic number, a critical cut-off point, shown in Fig. 5, represents a threshold value of the primary stage and the stable stage.

This sample is a standard sample, measured with different radiations, a number of instruments, varies scanning routines and sample shapes.
But due to the instrumental pole figure window only a selected number of grains were detected.
The continuous scanning in combination with an area detector includes all grains of the investigated volume; in our case all grains of the Al7020 test sample.
It has to be pointed out that step scan mode for high number of steps (sharp texture) is extremely time consuming and is done seldom.
Acknowledgement This work has been funded by the German Ministry of Education and Research (BMBF) under the contract number 05KN7MCA.

Numbers of large scale polders are constructed to protect low-lying coastal area of Sundarban in Bangladesh during 1960s.
The tests included grain size analysis, compaction characteristics and consolidated undrained direct shear test.
Grain size analysis was performed to determine the percentage of different grain sizes.
Since, different grain sizes affects the engineering properties of soil and influence soil classification, grain size analysis provided the required grain size distribution.
Table 1a: Grain size distribution parameters obtained from laboratory tests Borehole No.

The analysis of the main elements distribution and their combining over grains with the help of electron-probe microanalysis (EPMA) was investigated.
Nitric acid is a strong oxidant for refractory sulphide ores, and a number of technologies for applying of this reagent have been described in the literature [[11]-[14]].
Distribution of elements along the grains and their combination: a) initial sample surface image; b) Si distribution by grains; c) S distribution by grains; d) As distribution by grains; e) combining the spectra of Si, S, and As.
A number of studies confirms [[18]-[19]], at nitric acid leaching, sulfur may transform into the elemental form and can partially limit the dissolution of sulphide minerals due to the high oxidation potential during the pyrite and arsenopyrite dissolving, hence it restricts further dissolution of gold by cyanide solutions.

Several diffusion and permeability tests have been performed on non-uniform sand specimens having different grain size distribution.
In the last few years, a number of authors have reviewed this concept in detail [1-3].
The ionic flux from the source to the collector containers through the porous specimen was estimated by pipetting a number of liquid samples (0.1 ml with a micropipette) from both containers at successive time intervals.
(12) where, dh-max is the hydraulic diameter based on the maximum grain size present in the sample of diameter dmax [m] and α is a function accounts for the filling effect of the small grains for the void space between the large ones.
A number of permeability and diffusion tests on various samples having different grains size distributions have been used.

Wood machining grades of WC have a grain size of ~0.5 µm, which is ideal for producing sharp cutting edges [7].
The microstructure was observed by SEM to determine grain size and porosity.
The average grain size was observed to be below 1 µm for all of the samples.
Bright grey areas: SiC grains; Darker grey areas: β-Si3N4 grains.
Part of this work was supported by the Swiss Commission for Technology (CTI) under contract number 6894.2 IWS-IW.

Number of FSP passes and ambient conditions during FSP are among other factors affecting the process results.
Further, finest grain structure amongst the investigated cases was observed for FSPed AZ31 accompanied by undersurface cooling viz.
The possible reason for the same may be the grain size refinement as well as the presence of hard second phase TiC particles.
As mentioned previously, the grain size got considerably refined during FSP.
The recrystallized grain size produced during FSP supplemented with external cooling was smaller than that of with natural cooling.

These phenomena suppress further grain refinement of nanostructured copper, resulting in the saturation of grain size in the range of 200 - 400 nm and hardness around 140 HV [5].
The yield stress σ0.2 and tensile strength σUTS of the CAC304 increased with increasing the number of the HPT rotations, and reached the yield stress σ0.2 of 1050 MPa and the tensile strength σUTS of 1110 MPa by 5 HPT rotations.
In the case of metallic materials with bcc structure, the strain-rate sensitivity m usually decreases with decreasing grain size [12].
Acknowledgments This research was partially supported by JSPS KAKENHI Grant Number JP16K18259 and a Grant-in-Aid from Japan Institute of Copper.
Kato, Inverse temperature dependence of activation volume in ultrafine-grained copper processed by accumulative roll-bonding, J.

In presence of liquid phase, around the spheroidal grains, during a deformation process, a drastic decreasing of interactions and friction between grains occurs.
For factors related to continuous variables, as in this case, the following transformation has been used: 2 ii X X X ξ − = ⋅ ∆ (1) At the low level it is usually coupled the conventional number -1 and to the high level the number 1.
A microstructure with better mean grain dimension has been observed in the three central tests, while the Vickers micro-hardness values have not been the best ones.
The analysis of the influence of the mean grain dimension has produced a response in which the p-value is small.
The regression model for the mean grain dimension is therefore good.