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During the SMAT process, the metal surface was shot-peened by a large number of stainless steel balls.
The microstructure is characterised by uniformly distributed equiaxed nanometer scale grains (grain size in the range of 50nm to 100nm).
At the depth of 80m, there existed a large number of submicrometer scale grains (up to 0.3m).
At a depth of 220m, apart from some submicrometer scale grains there were also a few large grains in the size of 1-2m.
The grain size ranged from 50nm to 100nm.

Literature [3] idea of coarse-grained parallelism designs and implements the "satellite model" Particle swarm optimization.
LSSVM optimized by IPPSO Parallelization of PSO is divided into two different ways which are coarse-grained and fine-grained.
Literature [5] which uses idea of coarse-grained designs and implements "satellite" parallel particle swarm algorithm.
Core idea of Coarse-grained parallelism of PSO is to divide the population into several subgroups, and each subgroup separately conducts particle swarm algorithm.
The number of iterations is 2000 times. ，; ; , .

The surface preparation steps can permeate the pores and conformal CdS growth can be seen on the grain surfaces.
Therefore, it is likely that the grain boundaries are inverted, and have therefore n-type conductivity.
This is expected to result in a Voc loss of some 200 mV as Voc scales as the logarithm of the number of recombination centers.
One can now compare dense, vacuum deposited CuInS2 to porous, large grains, electrodeposited CuInS2 and to nanoporous DSC.
CdS deposition can be observed on the grain boundaries.

The results showed that tensile properties of the welded specimens were lower than those of base metal due to coarsening of the matrix ferrite grains and loss in the fraction balance of ferrite and austenite phases in the weld metal zone, where fracture took place.
Although HE in DSSs has been studied to some extent [3,4], the major reports are restricted in the base metal; only a limited number of studies have been made on the weld joint of DSSs.
Comparing the low magnification microstructures, M(a), H(a) and L(a), it is found that the ferrite grain size increases with increasing heat input (decreasing velocity); grain size is largest in L(a), medium in M(a), and smallest in H(a).
In specimen H, austenite phase exists as plates covering whole ferrite grain boundaries and as small island-shaped particles inside the ferrite grains.
The microstructure of specimen L is similar to that of specimen H, but austenite does not cover the whole ferrite grain boundaries.

It is found that as the coating thickness increases mean grain size increases.
As thickness increases, since smaller grains tend to have surfaces with sharper convexity, they gradually disappear by feeding the larger grains [11].
Thiel: Patent Number: US6413581B1 (2002)
Honjo: Patent Number: EP1081108A1 (2001)
Hurst: Patent Number: EP 254870A2 (2002).

Processing by route A resulted in a stronger texture evolution because of monotonic increase in strain with the number of passes.
The grain size measurement shows that the sample processed through route BC has the smallest grain size [18].
Equal channel angular pressing of the alloy 2014 leads to grain refinement because of continuous shearing of grains along shearing direction with number of ECAP passes.
The grain refinement is more in Route BC compared to the other routes of ECAP. 2.
Langdon, The principles of grain refinement in equal-channel angular pressing, Mat.

At the same time, there are many large angle grain boundaries in the steel hindering the crack propagation.
The number of effective specimens in this test was 22, with a total of 11 sub-sample pairs.
Due to the existence of a large number of dislocations inside the crystal grains, the crystal lattice at the tip is severely distorted during the crack propagation process, which hinders the crack propagation and reduces the crack propagation rate.
In addition, there are a large number of high-angle grain boundaries in δ-TRIP steel, which further hinders crack propagation.
In addition, δ-TRIP steel has a large number of high-angle grain boundaries, which further hinders crack propagation.

The number-based mean grain size was obtained from TEM images by two methods: (1) a linear intercept method, where ~50 lines were drawn in perpendicular directions, and (2) the maximum dimensions of 400 individual grains were measured, which also generated distributional histograms.
Although most of the grains were less than 300 nm, there was a large range in grain size and some were over 1 μm.
Material View Point Measurement Method Dimension 1 Dimension 2 Mean Aspect Ratio Axis (nm) Axis (nm) (nm) Forged Disk F Linear intercept N -- N -- 461 ~1 Individual grains* N 462 N 444 453 1.04 N Linear intercept N 448 F 239 343 1.88 Individual grains* N 460 F 246 353 1.87 Rolled Plate F Linear intercept R 490 N 417 454 1.18 Individual grains* R 502 N 421 461 1.19 N Linear intercept R 473 F 230 351 2.06 Individual grains* R 492 F 233 363 2.11 R Linear intercept N 431 F 231 331 1.87 Individual grains* N 412 F 237 325 1.74 * obtained from a total of 400 grains.
A predominantly UFG structure was retained, although a significant population of coarser, micronsized grains imparted a bimodal aspect to the grain structure.
Lavernia, in: Ultrafine Grained Materials IV, edited by Y.T.

ECAE provides a capability for achieving substantial grain refinement in metallic alloys and thereby producing materials having ultrafine grain sizes in the submicrometer or nanometer range [4].
ECAE processes achieve grain refinement through the introduction of severe plastic deformation.
Significant grain refinement has been demonstrated in a variety of magnesium alloys.
The hardness of the ECAE treated specimens with and without laser melting treatment increase with the increase of pass number.
The friction coefficients of the specimens with only ECAE and with laser melting treatment decrease with increasing pass number.

Introduction The key aspect of semisolid forming technology is preparation of semisolid alloy feedstock with fine spheroidal grains.
On the other hand, some nuclei will be remelted by superheated melt with only a small number of nuclei surviving.
In Fig.3 (b), spheroidal grains are dominant and free of rosettes.
The morphology of Fig.3 (c) comprises a large number of granular grains, a relatively small amount of rosettes and short rodlike arms.
Consequently the number of primary phase is more than that gained at a smaller reversed cone angle under the same pouring temperature.