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The results showed that grain size and domain size were small before HT,there was  high-density dialocation in the alloy.After HT,grain size  increased, the internal stress, dislocation and other defects were reduced,magnetic domains became wider,the number of the domain decreased and the exchange energy between the magnetic domain reduced,leading to the decrease of the coercivity and increase of permeability.It was also found that the curie temperature was not changed after heat treatment.
As to the grain size, the large grain size is preferred due to the decrease of the coercivity [10,11].The grain size increased and the area of the grain boundary reduced after heat treatment, reducing moving resistance of the domain wall and increasing movable distances of the domain wall in grain.
The grain size increased after heat treatment, making the coercivity(Hc) lower.
(2) The number of domains  reduced with the domain becoming larger,the exchange energy between magnetic domains and the energy of magnetocrystalline anisotropy reduce, which reduced the coercivity and increased the magnetic permeability
Interactive Effect of Grain Orientation and Grain Size on Magnetic Properties of Fe–78 wt% Ni Ribbons.

Therefore, the stored energy density of the grain which the site i in the MC-Potts model locates in, namely the stored energy per unit volume, Hi can be express as [10] (1) where Hm is the average stored energy density in MC computing domain; di, dm are the equivalent diameter of the grain which site i locates in and the average equivalent diameter of grains in the computing domain respectively; K is the constant used in describing the position of site i, which locates on grain-boundaries,and in grains,; si, sj are the orientation numbers of the grains which adjacent site i and j locate in respectively; is the Kronecker function related with the grain orientation number, in grains,and, in grain boundaries,and; the number of sites j adjacent to site i.
Nucleus numbers.
The site space dMC=1μm, the average equivalent size of initial grains d0=25μm and the total orientation numbers Q=180 were set up.
When ending the second MCS (2MCS) computing in △t2, the number of DRX grains is not only more than ending 1MCS computing in △t2, but also the DRX grains generated in 1MCS grow up in varying degrees, and the boundaries of growing grains majorly migrate towards the high-energy deformed grains (see Fig.4d).
The recrystallized grains generated in △t1 are very small, and their numbers also are very few.

Such materials possess an inhomogeneous microstructure especially after a small number of ECAP passes which makes it necessary to use a high-resolution 3D method for microstructure characterization.
All voxels that form one grain have a misorientation below 5°.
The optimal number of voxels for defining a grain is selected ten.
Misalignment of the sections can cause small grains, which do not actually exist, to be included when less than ten voxels are considered while more than ten voxels would cause small grains which are typical for ultra fine grained material to be excluded.
The true grain volume was calculated by Vgrain=Nv.Vvoxel (2) where Nv is the number of voxels and Vvoxel is the Volume of voxel.

Introduction Equal channel angular pressing (ECAP) is the representative model technique of severe plastic deformation (SPD) refining the grain size of metallic materials down to the sub-µm level, so called ultrafine grained (UFG) materials.
In the flat area, individual grain did not appear explicitly, and grain boundary sliding (GBS) hardly occurred across the boundaries.
The flat areas seemed to be agglomerates of grains having low angle boundaries.
In addition, a number of boundaries were well-defined, and showed sharp offsets of marker lines.
The deformation mode was changed from dislocation viscous glide to grain boundary sliding by additional rolling resulting in the development of larger portion of high angle grain boundaries. 3.

The preliminary observations data show complex temporal and seasonal variation in estuarine flocculation of fine-grained sediment.
Introduction Approximately 90 percents of the suspended sediment load transported from the Yangtze River to its estuarine and coastal areas consists of fine-grained particles with dispersed medium grain size of smaller than 32 μm.
Flocculation processes change physical characteristics such as original size, density and settling velocity of fine-grained sediment [1].
In other words, below the critical τ, the increased τ could promote the suspended sediment re-flocculation to large flocs by increase number of particle collisions per unit time, and lead large suspended sediment flocs break-up to small ones above the critical τ.
Estuarine macroflocs and their role in fine-grained sediment transport [D].

By this method, the material grain size can be refined to 20~200nm, which are nanometer level.
Fig. 5(a) is a line chart of the effective strain of these seven points when the number of torsion is 0.5, 1, 1.5 and 2.
The grain gets finer and more homogeneous when the number of turns increases [7].
This is the reason for the central area owns a larger grain size but edge area owns a smaller one.
This inhomogeneity gets smaller, and the strain increases with the number of turns increases which get the grain refined.

The grain size of sample processed by multi-pass ECAE was reduced with the extrusion number.
The EP shifts to more positive values with increasing the ECAE pass number until four-pass.
It is noted that the grain size of multi-pass ECAE samples decreases with the ECAE pass number.
Effect of the number of ECAP pass time on the electrochemical properties of 1050 Al alloys.
Corrosion resistance of ultra fine-grained Ti.

It is suggested that the large numbers of precipitates of Nb(CN) in the steel makes the structure transmissibility more serious.
The asymmetric prior austenite grains (PAG) are clearly outlined by the grain boundary allotriomorphic ferrite (GAF), whose size is between 50-200µm.
Large numbers of fresh austenite nucleus come into being and destroy the orientation relation of PAG, so that the structure is refined apparently.
Accordingly, refinement effect will gradually decrease until completely disappear along with the increase of cycle number.
(2) Large numbers of precipitates of Nb(CN) in the CFB/M-Nb steel makes the structure transmissibility more serious

Uniform fine-grained microstructures with the average grain sizes of 0.7 and 2.5 µm, are almost fully evolved at high ECAP strains at 250 o C and 450 o C, respectively, while ECAP at 300 o C (~0.6 Tm) leads to the formation of bimodal grain structure with fine grains of around 1 µm and relatively coarse grains of around 8 µm.
This picture becomes yet much more complicated by looking at some heavily-alloyed Al alloys, in which dynamic recovery is additionally inhibited by the presence of large number of dispersed particles and/or substitutional atoms in the solid solution [e.g. 13,4,6,8,9].
The other grain component is composed of relatively coarse grains of about 8 µm and the volume fraction of about 0.6.
A gradual increase in the number and misorientation of the boundaries of deformation bands and their conversion into HABs can result in the development of the new fine-grained structure through cDRX [13].
Coarse-grain formation at 300 o C.

It was found that creep behaviour is strongly dependent on number of ECAP passes.
Fig.2 shows Vickers hardness HV as a function of the number of ECAP passes.
This difference consistently increases with increasing number of ECAP passes.
Increasing elongation together with increasing number of ECAP passes indicates that high-angle grain boundaries have a lower strengthening effect under creep than low-angle ones.
High-angle grain boundaries were formed with increasing number of ECAP passes and actively influence creep properties.