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These small crystal grains exhibited textured structure when the electrolyte contained an organic sulfonic catalyst.
Thick black lines correspond to micro-cracks, and thin white lines correspond to grain boundaries.
Number of cracks formed during electroplating roughly increase with the amount of catalyst.
These results are consistent with the results by OM observation, and number of cracks formed during electroplating increases with the amount of catalyst.
(4) Number of surface cracks formed during electroplating roughly increase with the amount of catalyst.

Among these mechanisms one should list the followings. (1) The dislocation hardening associated with dislocation storage in the grain interior. (2) Hall-Petch or grain boundary (GB) hardening which is associated with grain fragmentation and with the barrier effect of GBs for dislocation movement
We say that "the number of small" when the structure is not yet converted into the granular type with prevailing high-angle grain boundaries.
There has been a plenty of evidence in the literature that the high-angle grain boundaries tend to form in f.c.c. metals at considerably higher strains (number of ECA-passes) than we imposed in the present work [2].
Surely, the number of passes which is required to form the high-angle grain boundaries is different for different materials, being dependent on various metallurgical factors such as the stacking fault energy, for instance.
Zehetbauer: in Ultrafine Grained Materials II / Y.T.

The K2O isometric replaces Na2O at the same time the Al2O3 isometric to replace SiO2, reduced the grain size.
In contrast, the content of [AlO4] will increase by 4No, which further result in a significant decrease of the number of discontinuous points in the glass network.
It is found that the main crystalline phase are Na4Ca4 (Si6O18), in addition to a small number of Na6Ca3Si3O18 and Ca3Si2O7 crystals, which indicates that K2O and Al2O3 don’t affect the species of the main crystalline phase.
As show in Fig.4 (c), small equiaxed grains formed in the AA samples , which is because the glass viscosity increase due to the replacement of part of SiO2 by Al2O3, so that crystal growth rate slowed down, and the more smaller equiaxed grains easily form, the average grain size is about 0.3μm.
Fig.4 (d)show that the large amount of small equiaxed grains formed in the AKA samples, there are many kinds of crystalline in the AKA samples by the XRD analysis, many kinds of crystal grow at the same time in the certain space, which make the probability of collision with each other increase, the collision of these crystals hinder the fast growth of crystals, so that the crystal cannot develop into flakes or needle, but form equiaxed grains, the average grain size is about 0.43μm, the grain size of glass-ceramics samples are listed in Table5.

Multi-peak reflections and/or sharp change in the value of Ω indicate the presence of misoriented grains.
In order to study the overall crystalline quality of the substrates, rocking curves are measured in a large number of spots on the wafer surface, and a two-dimensional map is generated.
Multi-peak reflections and/or sharp change in the value of Ω indicate the presence of misoriented grains.
From this, the contribution from the sub-grain misorientation to the overall reflection broadening is approximately 49 arc-seconds.
Rocking curves measurements performed on a large number of substrates showed that different surface finish on different wafer faces could cause wafer warp and a small but detectable degree of lattice curvature.

It has been shown that the grain size and segregation of Si, Cu and Mg atoms from the solid solution in the grain boundaries area are the main factors that enhance the alloy strength.
SPD techniques allow realizing a number of strengthening mechanisms.
As a result a structure with an average grain size of about 100 nm and mainly with high-angle grain boundaries (NS state) was fabricated.
Konrad, in: Ultrafine-Grain Metals, edited by J.
Armstrong, in: Ultrafine-Grain Metals, edited by J.

At lower sintering temperature of 1150°C, the dominant phase was rhombohedral which matches with JCPDS file number 73-2022 while tetragonal phase (JCPDS file number 33-0784) became dominant at higher sintering temperature (1200 - 1250°C).
The grains of all samples had regular shape with clear grain boundaries.
Thus, larger content of the grain boundaries obtained in the sample with smaller grain size can improve hardness value.
This result was partly attributed to the grain size effect.
For ceramics with smaller grain size, smaller number of domains or, in same case, even a single domain can form inside each grain.

Also nano-structured Dy doped CeO2 sintered bodies in the present study had wide ionic domain and high transport number of oxygen.
The average grain size in the sintered body was calculated using the linear intercept method measuring more than 200 grains using SEM.
The ionic transport number of oxygen, ti, was estimated as a ratio of observed emf to the theoretical emf.
The conductivity decreased with decreasing grain size and reached the lowest value at an average grain size of 237nm.
The n-type conduction appears because the number of conductive electrons is increased by a reduction of CeO2.

Until recently, the severe plastic deformation (SPD) just above Ar3, which enables the strain induced dynamic transformation (SIDT) of the unrecrystallized austenite into ultrafine grained ferrite, followed by the accelerated cooling preventing the grain growth, has been considered [1-5].
Ultrafine ferrite grains are shown in Fig. 5(a) and (b).
It becomes severer with increasing number of pass and cooling rate, and decreasing rolling temperature and test temperature [5,6].
SIDT ultrafine ferrite grains, and second phases aligned along the rolling direction on rolling plane, were observed.
[4] "Development of High Strength Structural Steel with Fine Grain (III) ", POSCO Report, 2001

Structure and size of grain.
Heating speed and grain size.
After water cooling the structure consists of a small number of proeutectoid ferrite, martensite and bainite [16].
Ferrite development occurs at a border of fine-grained austenite due to a fast cooling and elastic stress occur at bainite and martensite crystals development in this ferrite will be increased number of locations [17-18].
Number of cycle Grain size, [microne] 1 35–40 2 12–17 3 5–10 Upon completion of third cycle the pipe were heated up to 500°С in order to provide a proper steel grade and stress relief arising as a result of accelerated cooling.

Unlike base metal that has coaxial grain structure, weld metal is composed of a dendritic structure.
Grain growth in the heat affected zone did not occur.
Final microstructure and mechanical properties of weld and heat affected zone will depend on the heating and cooling rates and the number of times a particular region experiences the thermal cycle.
Grain growth in the heat affected zone has not happened, but very small precipitations have deposited.
Some precipitations have been deposited at grains and grain boundaries of heat affected zone.