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Both M23C6 and M6C can be found on grain boundary after thermal exposure in CM247LC.
During service of the bucket, MC decomposes slowly, yielding carbon which induces a number of important reactions.
On grain boundary, as shown in Fig. 5 (c), both M23C6 and M6C formed after MC decomposition.
(a) Scriptal MC, (b) blocky MC near γ-γ' eutectic, (c) MC on grain boundary.
Both M23C6 and M6C can be found on grain boundary as the result of MC degeneration in CM247LC.

The EBSD results show that grain boundaries in ferrite are basically high-angle grain boundaries (HAGBs).
A number of plants around the world are already practicing this technology.
This causes a corresponding increase in the undercooling, which results in an increased nucleation rate at both ferrite grain boundaries and grain interiors.
Due to the enhanced nucleation density at high cooling rates, grain growth is restricted by mutual impingement, which results in a finer ferrite grain size.
It can be calculated that grain size is about 13�m.

However, conventionally extruded Mg alloy sheets behave poor mechanical properties due to the strong basal texture and thus limited number of available plastic deformation modes.
The grain size of alloy is about 20μm.
Moreover, fibrous grain size remains near the top strain of tiny grains.
The DSE samples are behaved by inhomogeneous microstructure with finer DRX grains embedded in elongated deformed grains.
DSE process was much more effective in grain refinement.

The grain sizes have been evaluated.
All these results show that the grain sizes increased while the optical band gap decreased with increasing the thickness of CdS films.
A large number of studies are carried in order to produce CdS thin films with good structural and optical properties suitable for photovoltaic applications.
Table 1 Comparison of grain size of CdS thin films evaluated from XRD and SEM spectra Sample [°] [°] Peak intensity XRD grain size [nm] SEM grain size [nm] a-4 min 0.276 26.552 2886 56.2 60 b-8 min 0.230 26.644 6156 67.5 70 c-16 min 0.184 26.552 15650 84.3 90 a (4 min) b(8 min) c(16 min) Fig. 2 The SEM micrographs of CdS thin films at different Sputtering time Transmittance spectra of as-grown CdS thin films were shown in Fig. 3.
The crystallinity of CdS films were improved and the grain size increases with increasing sputtering time, while the optical band gap of CdS films decreases.

After the images capture, a grain amount of 1000 grains per sintering condition was analyzed using IMAGEJ free software image analyzer [8].
This behavior is probably linked to the exaggerated grain growth.
Grain size suffers a considerable increase in samples sintered at 1600ºC.
With the grain size increasing, the grain population under martensitic transformation decreases, which reduces the material toughness capability [3,4].
Furthermore, the secondary mechanism of zirconia toughening by crack deflection loses its capacity, for the number of deviations by the grain boundaries is decreased.

The main model parameters are the interfacial energy for nucleation, total number density of nucleation sites and preferential nucleation sites (homogeneous nucleation in the matrix, at dislocations, and/or at grain boundaries).
Outputs of this model are volume fraction, number density, mean size, and size distribution of precipitates.
The model predicts the recrystallized grain size and the volume fraction of recrystallized grains.
During 10 hour soaking at 510ºC, the number density decreases significantly due to dispersoid coarsening.
A small number of nuclei were considered to originate from grain boundaries (<10%).

The columnar β grains and fine acicular α formed during cold overlapping were denser than during heat overlapping.
Numbers show the sequence of overlapping cladding and arrows represent cladding direction.
The average width of β grains of heat overlap is 150-200μm and that of cold overlap is 100-150μm.
Fig.6 shows the SEM photos of acicular α and Widmanstaten α lath in the β grains of two overlap ways.
The lower ratio results the bigger grain generated.

It is well-known that the characteristics of the crystalline structure such as grain size, grain distribution and phase composition are determined by the parameters of crystallization and other accompanying processes that occur on heating the alloy, for instance, structural relaxation, grain growth, etc [2–7].
One may see that the number of peaks and the ratio of their intensities were similar in the amorphous and crystalline states (compare Fig. 2 and Fig. 3).
HPT not only leads to grain refinement, but is also able to increase the density of dislocations.
In a polycrystalline alloy, phase solution, recovery, recrystallization and grain growth may occur during heating.
%Ni, only recovery processes, recrystallization and grain growth may occur.

Such cations are capable to segregate at the grain boundaries (GBs) of ZnO to form secondary phases [7-13].
The photographs show blackish grains of ZnO phase and whitish entities of Gd2O3-rich phase residing mainly at GBs of ZnO grains.
At sintering temperature 1200oC increasing Gd2O3-doping from 0.5% to 6%, the average size of ZnO grains decreases from 15 μm to 4 μm, respectively.
Segregation of Gd ions at the GBs inhibits growth of ZnO grains and decreases the grain size; this will increase the number of the grains so the number of GBs, which leads to increase the values of E0 and decrease the leakage current, see Fig. 6.
The contact area of ZnO and Pr6O11 + Gd2O3 phases considerably increased becomes thicker and the whitish phase insulates some of ZnO grains from each other.

Base is large number of indentations and their statistical treatment, Fig. 1.
Basically, a large number of indentations is performed and automatically analyzed to obtain hardness, Young’s modulus and eventually other mechanical properties.
The mechanical properties in HR 45 steel were evaluated in 11 ferrite grains and 8 pearlite grains.
In DP 600 steel the mechanical properties were evaluated in 11 ferrite grains and 7 martensite grains.
Fine-grained steel absorbs more plastic work than coarse-grained steel, Table 2.