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In comparison, only a small number of such reports are available on cast materials.
Although ductility improved with higher numbers of working cycles, the strength decreased.
However, since a limited number of reports relating the fatigue properties to the presence of fine grains are available, the relationship between fine grains and various mechanical properties must also be elucidated.
The ratios of high-angle grain boundaries with misorientations of 15° or more for the as-received cast (measured area = 1500 µm x 1500 µm) and extruded materials (600 µm x 600 µm) are 90% and 85%, respectively, and the ratios of twins to these numbers are 55% and 5%, respectively.
However, the maximum stress amplitudes at low numbers of cycles were 25 and 40 MPa, respectively.

In the process of grain stocking, in grain pile, some concrete conditions such as temperature, grain moisture and air humidity could cause grain heat and blight which exert unnecessary loss on grain depots.
When the abnormality of grain state occurs, to ensure the safety of grain storage process, some corresponding measures could be taken.
To inquire the temperature of a certain point, before conducting temperature query it is necessary to determine the serial number of this point.
Therefore, it is essential to search for all the globally unique 64-bit serial number of DS18B20 on single bus before measuring temperature.
Interworkging diagram Digital humiture sensor is applied in grain measurement and control system to gather temperature of grain.

The grain boundary ensemble formation in UFG materials and its evolution under thermo-mechanical treatments The current use of electron backscattered diffraction devices recording misorientations of a large number of grain boundaries allows revealing that the grain boundary ensemble of SPD-processed UFG materials contains an entire spectrum of low- and high-angle boundaries.
In the range of high-angle misorientations the total number of grain boundaries with misorientation of 45–60° is observed to increase (Fig. 3).
The nucleation of new grains induced by grain boundary diffusion fluxes of Ni is supposed to change the spectrum of grain boundary misorientations in UFG molybdenum.
It should be noted that the nucleation of new grains at triple junctions and migration of grain boundaries due to the grain boundary diffusion of Ni were earlier observed in coarse-grained molybdenum as well [19].
However, the latter type of loading induces opposite changes in the fraction ratio thus decreasing the number of low-angle boundaries and increasing the number of high-angle boundaries.

However, the relationship between the intensity of the Bauschinger effect and the grain size that varied with the number of passes of ECAP was not shown clearly.
Distributions of misorientation angle after various numbers of ECAP passes.
Subsequently, the yield and flow stresses slightly increase with the number of ECAP passes.
Fig. 6(a) shows the changes in the proof stresses and with the number of ECAP passes for the TC and CT tests.
Results after different numbers of ECAP passes: (a) proof stress and ; (b) average grain size and .

A number of SPD processes such as accumulative roll-bonding (ARB) [2-6], equal-channel angular pressing (ECAP) [7], and high-pressure torsion (HPT) [8] have been developed to produce ultra-fine grained (UFG) structures.
Such strain-rate dependency became more obvious with a larger number of ARB cycles.
Figure 3(a-c) shows the grain boundary maps of the AA8011 specimen ARB-processed at various numbers of cycles.
The distributions of the grain boundaries determined by the FE-SEM/EBSD analysis are summarized in Fig. 3(d), where it can be clearly seen that the fraction of high-angle boundaries increases with higher numbers of ARB cycles.
The total elongation experimentally obtained and that calculated from Eq. (1) as a function of the number of the ARB cycles.

The specimens were observed under an optical microscope and a number of pictures were got in order to study the grain size.
The number of grain size in HAZ of the 3 group is counted.
The average statistics of grain size number are shown in Table 4.
From Table 4, it can be observed that grain size numbers of all the areas tested were larger than 6.
Table 4 Grain size number Zones Group HAZ-1 HAZ-2 HAZ-3 HAZ-4 A 6.54 6.96 7.07 7.09 B 6.45 7.34 6.98 7.08 C 6.37 7.05 6.44 7.06 Comparing the grain size in A, B, C, the 3 group, it can be obtained that as the heat input increases the influence on grain size is more obvious.

Introduction Nanocrystalline materials consisting of nanometer-sized crystallites contain a large number of interfaces, i.e. grain boundaries and triple juctions, which a large volume fraction of the atoms are associated with [1].
Such nanocrystalline electrodeposits are in non-equilibrium (metastable) states, i.e. high energy states due to a large number of interfaces [2, 3].
The temperatures Journal Title and Volume Number (to be inserted by the publisher) 3 corresponding to the exothermal processes are higher in Fe-Ni alloys than that in pure Ni, but the positions of the peak maxima are different depending upon the alloy compositions.
The fact that the <111>//ND grains are much coarser than the <100>//ND grains in the fully annealed specimen is attributed to the abnormal grain growth of the former in the early stages of grain growth.
Journal Title and Volume Number (to be inserted by the publisher) 5 (a) (b) (c) Fig. 5 OIM maps and the corresponding ND inverse pole figures in electroformed Fe-36%Ni alloy after annealing at 390°C for various holding times: (a) 0 min; (b) 5 min; (c) 30 min.

About five hundred grains were measured for each grain size distribution.
The number averaged SDAS and ferrite grain size values measured at several through-thickness locations for all the slabs, Table 3, indicate that the finest SDAS and ferrite grain sizes are near the top-surface, which experienced the highest cooling rates.
Al- and Nb-rich precipitates were often clustered together in regions of high precipitate number densities, whilst, Tirich precipitates, of size 50-200 nm, were generally found associated with Nb-rich particles.
However, the precipitate distribution was found to be more homogeneous on slab 3 (ratio between maximum and minimum precipitate number density values approximately 1.8 : 1 at quarter thickness position).
The number of these actually present for reheating to 1225°C is very low, which is consistent with the large grain growth that occurs as almost full dissolution of pinning particles takes place.

The main shafts, after final heat treatment, should have a grain size of number 5 or finer according to ASTM E112.
Table 4 Technological parameters of WHF method number of laps 1 2 3 4 5 6 7 8 height before drawing out 2860 3000 2420 2630 2180 2330 1970 2070 height after drawing out 2290 2400 1940 2100 1740 1860 1580 1660 reduction 570 600 480 530 440 470 390 410 tool width ratio 0.524 0.500 0.620 0.570 0.688 0.644 0.761 0.725 Heat treatment after forging, as shown in fig.2, includes three times normalizing and tempering in order to gaining fine grains.
There is a serious mixed grain phenomenon in the first technology (without Nb), which grain size is grade 2-5, as shown in fig.3, While the average grain size of the second technology (including Nb) is grade 8.2(fig.4).
The final average grain size is grade 7, as shown in fig. 5.
(2) The refined steel with VCD treatment results in grains growing up easily, but the correct heat treatment can fine grains effectively.

These concentration profiles are built up simply by determining the number of particles that have reached a given distance from the particle source after time t.
It is clear that a tracer atom need not sample a large number of grains and grain boundaries in order for its diffusion coefficient to be given by the Hart Equation (Eq. 3).
He used an f.c.c. lattice rather than the usual simple cubic lattice because it provides for a larger number of grain boundary orientations for a given mesh size.
A number of Monte Carlo calculations have been made in which grains are represented as cubes or as spheres in various configurations with and without segregation [24-26].
Ratio of Deff (as obtained from the Hart Equation) to Deff (as obtained from the Maxwell Equation) as a function of g for values of Dl /sDgb ranging from 10 -3 to 10 -8 (lines are marked with corresponding numbers).