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In both investigations the alloys were cold rolled and recrystallised to achieve similar starting grain sizes of nominally 100 µm and cube recrystallisation textures.
After one cycle the microstructure scale is still that of the start material with high angle boundaries (HAB's) being located only at the prior sites of the prior grain boundaries, indeed in Fig. 1 it can be seen that the width of the map only just spans the width of one grain.
After four cycles one can see that the prior grains have now aligned parallel to the rolling direction and that the substructure has also become aligned to the deformation direction.
As a function of strain the number of interfaces sampled increases, but by the same token, the width that each interface locally reduces map quality becomes narrower.
Tech. 16 (2000 ), p. 1246 [8] J.R.Bowen: The formation of ultra-fine grained model aluminium and steel alloys (PhD Thesis UMIST 2000)

The average grain sizes, which measured by a linear intercept method on the amplified morphologies of Fig. 1 (a) and (b), are in a range of 20 to 100 nm.
Fig.1 HRTEM micrographs of the as-spun (15 m/s) Mg20Ni10-xMnx (x=0-4) alloys: (a) Mn0 alloy; (b) Mn2 alloy; (c) Mn4 alloy The XRD profiles of the as-cast and spun Mg20Ni10-xMnx (x=0-4) alloys are depicted in Fig. 2, from which it can be seen that the melt spinning gives rise to an obvious broadening of the major diffraction peaks of the Mn2 alloy, to be ascribed to the refined grain and the stored stress in the Fig.2 XRD profiles of the as-cast and spun Mg20Ni10-xMnx (x=0-4) alloys: (a) Mn2 alloy; (b) As-spun (15 m/s) grains by melt spinning.
Fig. 3 Evolution of the capacity retaining rate of the Mg20Ni10-xMnx (x=0-4) alloys with cycle number: (a) Mn2 alloy; (b) As-spun (15 m/s) The cycle number dependence of the SN values of the as-cast and spun Mg20Ni10-xMnx (x=0-4) alloys is described in Fig. 3, revealing that the melt spinning and the Mn replacement notably ameliorate the cycle stability of the alloys.
On the other hand, the refined grain by melt spinning and replacing Ni with Mn is favourable to the discharge capacity because the grain boundaries possess the distribution of the maximum hydrogen concentrations.
It is indubitable that the diffusion of hydrogen atoms is markedly easer in a crystal alloy than in an amorphous one due to the fact that the large number of interfaces and grain boundaries available can act as paths for hydrogen diffusion [9].

The internal material structure (number and structure of phases, grain size and structure type) is the internal factor.
Increased grain size and number of phases result in significantly increased non-homogeneity of plastic deformation.
Similarly, Fig. 3 documents the influence of on ΔRe and Rm of steels C4 and E500TS with different grain sizes.
The grain boundaries are insuperable obstructions to dislocation movement, therefore the finer grain the more obstructions, and the steel is less sensitive to the strain rate.
Fig. 4 shows an example how the grain size influences the Re/Rm ratio at various strain rates.

However a number of questions remain on the effect of this type of laser welding on the mechanical aspects of the structures assembled.
The determination of residual stresses requires a number of steps: - Identification of crystalline phases The identification of crystalline phases is undertaken by indexation of diffraction peaks.
There are a number of reasons for this choice.
When a material presents a texture, the residual stresses were calculated with regard to the orientation of the grains: the ODF.
RESULTS Metallurgical results The laser procedure leads to a reduction in size of the grains in the weld zone and the presence of a high crystallographic texture only in the surface of the weld line, the main orientation of which is as follows: {101 1} 3 41 3 (58 % of the grains) [3].

Wilson [13], in studying the effect of spiral grain on the strength of wood, found serious deficiencies associated with the effects of spiral grain while investigating static bending, impact bending and compression parallel to grain.
All visible faces of the timber should be examined for slope of grain, as not all faces will exhibit the same extent of the slope of grain.
Wilson, The effect of Spiral Grain on the Strength of Wood, Jour.
Wilson, The effect of Spiral Grain on the Strength of Wood, Jour.
Anthony, A Grading Protocol for Structural Lumber and Timber in Historic Structures, Grant Number MT-2210-05-NC-05, National Center for Preservation Technology and Training, Natchitoches, LA, (2009)

From FTIR spectra, the variation in the peak intensity and shifting were observed which is due to the interaction between O-OH on the filler grain surface.
Al2O3 filler improved the conductivity by transient hydrogen bonding of migrating ionic species with O-OH groups at the filler grain surface.
This isotherm conductivity demonstrate a single maxima implying that a balance has to be maintained between increasing the number of charge carrier ions and decreasing of ionic mobility.
The Al2O3 filler assists in enhanced conductivity by providing transient hydrogen bonding of migrating ionic species with O-OH groups at the filler grain surface.

For the purpose of this test, as to the transition of test specimens from typical sandy soil to fine grained soil caused by the increase of silt particles and clay particles, the change point of strength is at 45％ approximately, which is basically consistent with the compacting test and CBR test, etc.
The test samples were mainly the eolian sand taken from the hinterland of Taklimakan Desert (Numbered as 0#) and the silt taken from the Populus diversifolia forest on the periphery of desert (Taken those ＜0.074mm , and numbered as 1#), mixed in different proportion.
Fig.1 Curve of Compaction Density Changing Along with Silt particle and clay particle Content Table1 Achievements of Test on Basic Properties of Test Samples Sample number Grain-size(mm) / percent of pass(%) Liquid limit Plastic limit 0.5 0.25 0.15 0.1 0.074 0.05 0.02 0.01 0.005 0.002 0# 100 99.7 97.9 63.1 16.3 1.1 0.3 0.2 0.1 0.1 28.6 22.6 1# 100 100 100 100 100 79.1 39.7 24.1 18.0 11.6 29.2 18.2 Methods and Thoughts Carried out test according to the “Direct Shear Test on Sandy Soil”(T0143-93) in the Test Methods of Soils for Highway Engineering[2](JTJ051-93).
In summary, as to the transition of test specimens from typical sandy soil to fine grained soil caused by the increase of silt particles and clay particles, the change point of strength is at 45％ approximately, which is basically consistent with the compaction test and CBR test, etc.
(4)For the purpose of this test, as to the transition of test specimens from typical sandy soil to fine grained soil caused by the increase of silt particles and clay particles, the change point of strength is at 45％ approximately, which is basically consistent with the compaction test and CBR test, etc.

The line intercept method [4] was employed to measure grain size and size distribution.
be attributed to a number of factors, including enhancement in temperature gradient, enhancement in transformation kinetics and possibility of increase in retained austenite fraction.
The normalized grain size distributions follow a log-normal distribution (see solid line; Fig. 7(a)).
The cumulative frequency as a function of normalised grain size along with the lognormal fit of ferrite grain-size distribution at various indicated cooling rates for Fe-5.93at%Ni, (b) the average grain size of ferrite at room temperature as a function of various applied cooling rates.
The normalized grain size distributions of the transformed specimens exhibited invariant nature, with reduction in mean grain size with increase in cooling rate.

Finite Element Analysis on low cycle fatigue properties of HRBF RC Pile Tip Fu Qian1,a, Liang Shuting1,b, Zhu Xiaojun2,c 1School of Civil Engineering, Southeast University, Nanjing, 210096, China 2 Architectural Design and Research Institute, Southeast University, Nanjing, 210096, China afuqian0117@163.com, bstliang@seu.edu.cn, czhuxiaojun9999@gmail.com Keywords: fine grained steel rebar; Low cycle fatigue; Nonlinear finite element Abstract.
The ultrafine grain steel[3-4] is a new generation of steel with the characteristics of high strength, high elongation, but good plasticity and toughness.
Parameters of Test Specimens Specimen Numbers diameter (mm) fc (MPa) Longitudinal reinforcement reinforcement ratio stirrup axial compression ratio ZS12-1 350 31.2 8B12 0.940% A6@100 0.2 ZS12F-2 350 31.2 8DF12 0.940% A6@100 0.2 ZS8F-3 350 31.2 10DF8 0.523% A6@100 0.2 Note: Vertical force determined according to axial compression ratio.
DF represents 500MPa fine-grain steel bars, B represents HRB335 steel bars and A represents HPB235 steel bars.

The grain size of ceramics gradually increases, the dielectric constant decreases first and then increases, the dielectric loss increases first and then decreases and the density reduces with the increase of tin ion doped amount.
From Fig.2, We can see that the grain crystal was uneven and polygons, size of parts grain particles in ceramic increased gradually, the porosity decreased and the density increased with the increase of tin ion doped amount.
With the increase of Sn4+ substitution amount, vacancies number increasing because the positively charged of oxygen vacancies combined with the negatively charged ions form a dipole, improved the ability of polarization under the electric field.
The grain size of ceramics gradually increases, the dielectric constant decreases first and then increases, the dielectric loss increases first and then decreases and the density reduces with the increase of Sn4+doped amount.