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Di Schino et al. [6] studied the effect of grain size on fatigue in a 17Cr-11Mn-1Ni-0.3N steel, and they found grain refining to not have a strong effect on fatigue life in this steel.
In contrast, a strong effect was shown for grain refinement for the fatigue life of AISI 304 stainless steel.
Each striation represents a load cycle, and the number of striations is equal to the number of load cycles.
The diameter and depth of the dimples are affected by grain size, the second phase particles, stress state and strain rate.
According to the size, depth and number of dimples, the plastic toughness of the test alloys can be determined.

This was followed by a number of investigations reporting varistor action in TiO2 with low breakdown field strengths [5-8].
The average grain sizes of samples were determined by the intercept method.
Most Y3+ ions segregated at the TiO2 grain boundary to relieve elastic strain energy and thus increased grain boundary resistivity by acting as an acceptor.
It can be seen form Fig. 2. that average grain size increase with the increase of sintering temperature form 1350 to 1450 ℃.
According to the boundary barrier model, the breakdown voltage , Eb, for a varistor is determined by the mean number of barriers n in series multiplied by vb, that is [12] : (2) where vb is the voltage barrier at a grain boundary, which is almost a constant for different samples.

Table 1 Rock mechanics parameter values order number E/Gpa v Φ/（°） C/Mpa （g·cm-³) The First 27.8 0.273 29.6 12.01 2.69 3# 0.2 0.450 25.0 3.00 1800.00 the third 17.8 0.230 28.3 10.00 2.64 Estimation method to determinate the paleotectonic stress level Another important aspect in stress analysis is to estimate paleotectonic stress level.
(3) Dynamically recrystallized quartz grain method When minerals are under relatively high temperature or heavy strain, dislocation creep will always occur, which is often accompanied by dynamic recrystallization, thus forming dynamically recrystallized quartz grains.
Metal and mineral experimentals show that there exists certain function relation between dynamically recrystallized quartz grain size and difference stress, its general expression can beσ1σ3=AD-M, in which A an M are material factor and D dynamically recrystallized quartz grain size (unit: μm).
Dynamically recrystallized quartz grain size can be calculated or statically measured under optical microscope or TEM and SEM
In the formula, S1 is decomposition shear stress coefficient, which has something to do with double crystallization degree of mineral grain and can be obtained from the relation graph (Figure 3)between double crystallization percentage of calcite and dolomite and S1. ζc is a constant number.

These grains were refined and we have seen fine grains in the weld nugget in about 6μm size, for sample No.4 (710rpm, 125mm/min).
Fig. 2 shows weld nugget grains of samples no. 4,7,10 and 13.
Fig. 2 shows that the grain size is increased with heat input.
The data show more elongation for sample number 4 compares with sample No. 1.
Moreover, the size and distribution of dimples is also affected by number and distribution of nucleated microvoids.

Fig.3 (a) and Fig.3 (b) are the SEM micrograph of Al8B4C7 grains in samples heated at 1700°C (N-1-5).
Fig.3 (c) and Fig.3 (d) are the SEM micrograph of Al8B4C7 grains heated in samples at 1700°C (N-2-3).
In addition, the shape of most grains in sintered samples was irregular, and there were also a few of grains having the shape of prism or sheet, the size of the grains were about several microns. 4 Conclusions (1) Assumed Al was the reducing agent, use aluminum, borax and carbon powders as raw materials can produce the composite materials contain Al8B4C7, and the final products were related to the temperature and the ratio of the raw materials
(3) Most of grains of particles were irregular morphology, but there are also a small number of grains have the shape of prism or sheet.
The size of the grains was about several microns.

Diffraction rings become more point-wise because of a decrease in a number of grains in the area of analysis (Fig. 8c).
Evolution of the recovery stress as a function of the number of cycles for Ti-50.26%Ni after e=0-2+400°C.
Arrows on the e = 0.3, TPDA = 350°C diagram indicate increase in number of cycles.
The number of cycles to failure and the accumulated strain are significantly lower after CR(1.2) and CR(1)+IA+CR(0.2).
The latter consists of two neighboring grains.

On this basis, introduced the island model, relative to the fine-grained has two quantum behavior of particle swarm，m optimization algorithm, the proposed two kinds of coarse-grained parallel based on multiple populations has the behavior of quantum particle swarm optimization (QPSO) algorithm.
is inertial factor, is a linear decrease from 0.9 to 0.6, ==2；is the random number ,that distributed evenly in between (0, 1).
and are the random numbers between in [0, 1]. is coefficient of expansion about the QPSO, and the only parameter of QPSO algorithm.
If same processor Pi, it also receive information from the X ', and using this information to replace one or a number of processors.
The number of particles in particle swarm sequence set to 40,80,120.

The highest value found in welds with root gap of 3 mm, followed by root gap of 6 mm, and 0 mm Hardness values in the welding area is higher than the parent metal and HAZ because the number of Si, Mn and Cu elements in the welding metals are bigger than base metal.
Microstructure of weld metals were Accicular ferrite, Widmanstatten ferrite, and grain boundary ferrite, while microstructure of base metal and HAZ were ferrite and perlite.
The number of elements increased in the welding process are Si, Mn and Cu.
(a) Gap 0 mm (b) Gap 3 mm (c) Gap 6 mm The microstructure of welding zone are Accicular Ferrite, Widmanstatten Ferrite and Grain Boundary Ferrite (Fig. 4).
The microstructure of weld zone are accicular ferrite, widmanstatten ferrite and grain boundary ferrite.

There have been a large number of literatures reporting on the changing characteristics of reservoir properties after thermal recovery [6-9].
Considering the good prop-carrying capacity, sand grain was produced out with heavy crude oil.
When the steam from injectors flows through the unconsolidated sandstone, the sand grain will drop out from the rock matrix.
Since 1980s, a number of researches are conducted about (thermal-) fluid-solid interaction, and most of them are based on the Boit’s consolidation theory.
During the period of steam flooding, the sand grain in reservoirs will drop out from the oillayers and move out with oil.

Coarse grained (CG) microstructured materials are very soft with a low strength and have a low wear resistance at dry sliding conditions [2].
An ultrafine grained (UFG) or nanocrystalline (NC) microstructure in soft metals (Cu, Al, Nb, Ta, etc.) can be formed with a help of SPD process.
Such process in material takes place by grain size (GS) decreasing at a simple shear stress by number of passes through the intersection or by increase in strain during equal channel angular pressing (ECAP).
SPD by ECAP was carried out by route Bc up to six numbers of passes at room temperature with a speed of 5 mm·s-1.
Cabrera, Thermal stability of ultrafine grains size of pure copper obtained by equal-channel angular pressing, J.