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The grain size decreased when the Ca content and sintering temperature increased.
The grain size of (Ba1-xCax)(Ti0.92Sn0.08)O3 ceramics decreased when the Ca content increased.
It also found that the two-step sintering produced a smaller grain size than those obtained from convention one.
Ca incorporation caused a decrease of the grain size and increase in Curie temperature.
Acknowledgements This research is financially supported by Prince of Songkla University under contract number SCI580905S.

A large number of studies have been performed to produce the ultra fine grains and make clear their formation mechanism in various SPD processes such as equal channel angular pressing (ECAP) [1], accumulative roll bonding (ARB)[2] and high pressure torsion (HPT) [3].
FRSP[4] is a straining technique which enables to make ultrafine grains with a strong preferred orientation in surface layer.
Commercial purity titanium (CP Ti, grade 1) and aluminum (A1050) sheets with an average grain size of 30 mm were used as starting materials.
This might be attributed to much more strain imposed into the HP Ti sample due to its larger grain size and less impurity.
This was attributed to more strain imposed into the HP Ti sample due to its larger grain size and less impurity

Introduction Because of high melting temperatures, high degree of covalent bonding and low self-diffusion coefficients of TiB2 and TiC, the achievement of full-density TiB2-TiC composites requires long exposures at high sintering or hot-pressing temperatures, so high processing temperature adversely affects the microstructure due to grain growth and also lead to high cost of the materials.
Recently, Zhao et al [2] introduces combustion synthesis into high gravity field to induce thermal explosion reaction, successfully prepared near-full-density TiC-TiB2 composites with fine-grain even ultra-grain microstructures by liquid forming and rapid solidification, and the selection of the additives was considered to one of key factors affecting the microstructures and properties of solidified TiC-TiB2 composites.
FESEM and EDS results showed that TiB2 primary phases were in the form of fine platelets in the ceramic were, TiC second phases presented the irregular grains, and white NiAl intermetallics was distributed at the boundaries of TiB2 and TiC grains, as shown in Fig. 4.
As mass fraction of Ni-Al composite additive was 5%, size distribution of TiB2 platelets in the composite was very uneven, at local region there were a number of coarse TiB2 platelets, and a number of cavities were also observed, as shown in Fig. 5(a).
XRD, FESEM and EDS results showed that the ceramic composites were composed of TiB2 platelets, irregular TiC grains surrounded by NiAl intermetallics.

Nonuniformity, related to mesostructural elements, such as general grain boundaries, special CSL boundaries Σ3 (twins), areas with high density of low-angle boundaries, is typical for radiation porosity.
EBSD Nordlys Nano detector by Oxford Instruments with analysis system was to determine orientation of specific grains and analyze local microstructure.
Results and Discussion Long-term exposure of neutron irradiation leads to formation of a large number Frenkel pair, vacancy and interstitial.
More detailed microtwins (CSL Σ3 boundaries) examination, carried out with EBSD technique, shows that the majority of uniformly distributed voids is detected in inner grain volumes, Fig. 3 a, b.
Kawai, Grain boundary engineering of austenitic steel PNC316 for use in nuclear reactors, J.

As an example of its use in aircraft parts, a large number of small holes need to be drilled in the surface of engine cowlings to reduce engine noise.
It has been found in previous research as a result of studying other processing methods that blasting can be used to effectively create a large number of small holes.1)2) However, there are a number of unclear points on the details of blast processing, regarding what sort of mechanism will open the right holes in the right conditions.
The abrasive used was mainly the commonly-used oxide alumina (WA #320) with oxide alumina (WA #600) with the grain size only changed, as well as silicon carbide (SiC #320) of the same grain size but a different material.
The depth of the hole was observed to increase each time the number of passes was increased for each specimen.
Fig.4 Processing section of every pass (laser microscope) 3) Fig.6 Erosion volume and the number of passes by each abrasive (media) Fig.5 Erosion volume and the number of passes in changing test specimen 3) 3.2 Measured erosion volume for different abrasive The abrasive used for all experiments was WA #320, but WA #600 with a different grain size and SiC #320 using a different material were used for comparison.

After the first co-extrusion, the individual pieces were bundled and co-extruded again, reducing the lateral size of each phase and multiplying the number of continuous monofilaments.
Several kinds of composites were produced with volume fractions of the zirconia phase of 10, 31, 47, 66, 88% by adjusting the number of each monofilaments in a feedrod.
The grain size of sintered samples was determined by the mean linear intercept method using micrographs of polished and thermally etched surfaces.
The diameter of the filaments was reduced to ~50 micron and the number of filaments was increased significantly, close to the theoretical value expected from number of extrusion.
The strength of the fibrous composites was almost the same as that of the monolithic alumina suggesting that the large alumina grains are likely to be the controlling flaws in these composites.

A large number of parallel bedding, one-way oblique bedding, small-scale cross bedding, the bottom scour structure and syngenetic deformation structure can be seen in the Fuyu oil layer.
(2)Grain size distribution characteristic the lithology in the study area is main fine-grained sandstone and siltstone, containing a small amount of medium sandstone and fine conglomerates.
Underwater distributary channel of delta front subfacies is main jumping component of the medium-fine grained sediments.
Fig.1 Diagram of reservoir sandstone type of Fuyu Fig.2 Probability cumulative grain size curves oil layer in the southern Fuxin Uplift of Fuyu oil layer in the southern Fuxin Uplift (3)Sedimentary structure Through the fine core observation of 22 coring well, a large number of fossils of plant roots, nodules , parallel bedding, a large one-way oblique bedding, small-scale cross bedding, horizontal (wavy) bedding and the typical sedimentary structures of the bottom scour structure and syngenetic deformation structures can be seen in the Fuyu oil layer and provide a basis for the restoration of its sedimentary environment
Although fine-grained sandstone, siltstone, muddy siltstone, silty mudstone and mudstone are the main, conglomerate, coarse sandstone content are also high.

The number and distribution of the second phases will be affected by heat tratments, different processes will affect alloy’s corrosion properties accordingly [3].
In the PA condition, a large number of pitting corrosion can be observed, along with obvious intergranular corrosion.
Alloy’s corrosion speed under PA condition was the fastest, result from alloy’s GP area changed into unstable β″ phase; Mg2Si phase separated in grain boundary combined together with other phase, forming a net, at the same time causing poor solute element layer near grain boundary.
The dark grey α matrix around Si was anode. α matrix was prior to corroded, while corrosion pit appeared along the grain boundary.
Conversely, if the matrix phase was anode phase, the second phase was cathode phase, the more number of second phase the higher of potential, the more serious corrosion of the alloy.

The structure of the unstrained material represents ferrite and pearlite colonies located in different parts of ferrite grains.
The facets are massive enough and are comparable to the dimensions of the structural components, such as ferrite and pearlite grains.
In addition, a number of hollows and facets with clear-cut borders were observed on the surface.
The facets are covered with fatigue striations while the orientation and dimensions of individual facets are comparable to the grain size.
With an increase in the fatigue crack growth rate, the step of striations increases, as well as the number of secondary microcracks.

Avrami type equations for the prediction of both the MDRX and SRX were adapted to feed a semi-empirical grain structure model.
However, recovery tends to become more important if the number of potential nuclei decreases [1].
The dynamic of the thermal control can not be increased arbitrarily because Journal Title and Volume Number (to be inserted by the publisher) 3 of the fixed heating frequency of 50Hz.
The short annealing time was chosen to avoid grain growth.
This lead to an initial grain size of 120µm.