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The density of the grains grown increases with an increase in the number of stress cycles.
Based upon this method, the relationship between the proper stress where dense grains or flecks begin to appear and the number of repeated stress cycles, and between the critical stress at slip initiation and the number of repeated stress cycles can be determined.
Ohshima [6] proposed a stress measurement technique using slip lines in copper foil with grown grains.
There are remarkable characteristics in grain boundaries in which recrystallization is apparent.
The plating foil thus obtained was split into a number of rectangular pieces, 2mm×30mm in size.

The average crystallite/grain size is observed to be at the minimum when the laser fluence is at 34 mJ/cm2.
Graph shows the variation in average crystallite/grain size due to different laser fluences.
In ferromagnetic materials with very small grains, due to the ferromagnetic exchange interaction, the magnetic moments are forced to align parallel, thus impeding the magnetization to follow the easy directions of each individual grain.
As a consequence, the effective anisotropy, Ke for the magnetic behavior is an average over several grains, (2) where N is the number of grains included by the exchange interaction length.
Hence, (3) where Dg is grain size.

The phenomenological approach proposed by Johnson-Mehl-Avrami-Kolmogorov (JMAK) is used to follow the evolution of recrystallised volume fraction with time t [7]: ( )                 −−= ∫ 3 0 exp1 t gb rex dtVN tX , (3) where Nrex is the number of nucleation sites, and Vgb is the average grain boundary velocity.
Vgb is taken to be the product of the grain boundary mobility M and the driving force G which is related to the stored energy from cold work.
Elements in solid solution will modify grain boundary motion, mainly through a solute drag effect, leading to a decrease in grain boundary mobility.
This is justified because the diffusion rates of tin and oxygen are faster than the calculated velocity of the grain boundary for this system.
The resulting expression for mobility is: 1 1 −         += solute solute pure C M M α , (5) where CSolute is the bulk concentration of solute in solid solution and αSolute is: ( )             −      = kT E kT E DE kTN b b b v Solute sinh 2 δ α , (6) where δ is the grain boundary width, Nv is the number of atoms per unit volume, D is the cross grain boundary diffusion coefficient of solute in Zircaloy-4, and Eb is the solute-grain boundary binding energy which is typically around 0.3 eV. [2] Hydrogen has a very specific effect on dislocation kinetics due to its very high mobility and to the large size effect associated with its elastic field.

An increase in grain size is observed with the increased calcined temperatures as well as the concentration of sol, while the specific surface area decreases from 50.3 to 13.2 m2/g.
The average grain size and interplanar spacing (d331 nm) of NiFe2O4 after sintering at different temperatures are listed in Table 1.
It appears that sintering at 600oC leads to a partially amorphous structure with a relatively small number of individual crystals (Fig. 2(a)).
The observed higher value of saturation magnetization can be explained based on grain size and the exchange interaction between the adjacent nanometer-sized grains.
The exchange interaction increased Ms in the material with densely packed grains [16].

Journal Title and Volume Number (to be inserted by the publisher) 3 micropipes (giant screw dislocations), which can be strictly proved by ray-tracing simulations [6].
Peak splitting due to grain boundaries in SiC substrate.
(c) SWBXT back-reflection image showing the grain boundary (arrowed).
Journal Title and Volume Number (to be inserted by the publisher) 5 misalignment of the analyzer has little influence on the accuracy.
Meanwhile, no noticeable small-grain boundaries were observed in the areas studied by HRXRD.

Because of obscured luminous flux and particle projection area is in proportion, and the amplitude of the electrical pulse signal of photocell is proportional to the change of the luminous flux, and electrical pulse signal amplitude reflect the size of the particle directly, the pulse number is the number of particles.
Figure 3.Fatigue spalling grain Figure 4.
Severe sliding grain Figure 5.
Ball mill grain Magnify the spectral slice for 500 times by ferrographic microscope, we can find medium amount of fatigue spalling grains, a small amount of severe sliding copper grains, and a little iron ball mill grains that exist in the spectral slice, which suggests that hydraulic components friction pair has a serious fatigue wear, and a adhesive wear caused by overload and excessive speed.
From figure 5 we can see that on the iron grain chain there are medium amounts of Fe2O3 grains, which is mainly caused by water entering into the hydraulic oil.

For large grain materials, nucleation sites are mainly grain facets and the dispersion is smaller but the fatigue life is generally lower [1].
Once the stabilized state is reached, a Smith-Watson-Topper scheme is used to calculate the number of cycles to crack initiation.
Because of grain size issues (grain size after heat-treatment is around 50 μm), the values beyond 80 µm were considered as not reliable and were omitted.
However grain size issues are reached beneath 80 μm, which make the sin² Ψ method unsuitable.
A single crystal method applied to individual grains, albeit time consuming, may be more suitable.

In order to calculate lahar velocity, distinguished the type of lahar by analyzing the grain-size distribution of lahar deposits.
In order to distinguish the type of lahar, analyzed the grain-size distribution of lahar deposits.
Analyzed the first group 6 samples with grain-size parameters method, acquired the meaning grain size, sorting coefficient, skewness and kurtosis of lahar deposits in Changbai mountain region (Tab.1).
According the result of grain-size parameters method analysis, the lahar deposits in Changbai mountain region was bad sorting, and depositing coarse group mainly.
According to our grain size analysis of the lahar deposits, lahar of Changbai Mountain is thin viscous debris.

It can be seen that the number of pores and the pore size reduced as the sintering temperature increased.
At the temperature of 1380 ℃(Fig.2(d)), the grain size became larger than that at the temperature of 1280 ℃ and pore size became smaller.
At the low temperature of 1280 ℃, grain growth had taken place.
As mentioned previously, the number of pores and the pore size reduced as the sintering temperature increased.
And lots of pores and isolated retained powder particles can be seen in these SEM images, while the number of pores and retained powder particles gradually reduced with the sintering temperature increased.

Three different regions were separately analyzed and were numbered in Fig.5.
Fig.4 Test samples cut from extruded bars Fig.5 Numbers of different texture and rails.
An interaction equation is introduced to relate single grains with HEM at infinity [5].
The basal and plane of grains tend to rotate toward the compressive direction.
Acknowledgement This research was sponsored by the Key Project of National Education Ministry with grant number 311017.