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The particle and grain morphology used scanning electron microscopy (SEM).
After calcinations at 600 o C, the precursor of BaCO3, SnO2, BaO, TiO2, BaTiO3 and BaSnO3 were detected, which agrees with the data listed in JCPDS file number 050378, 03-3174, 21-1272, and 06-0395, respectively.
These photographs show well-developed grain size and dense microstructure.
The average grain size is about 0.99 - 0.77 µm with sintering temperatures of 1250 - 1450 oC, Table 1.
The average grain size was increased with increasing sintering temperatures.

Average grain sizes of the studied samples decreased as the ratio of HA increased.
Regular grain shapes and grain boundaries clearly occurred for all samples.
The average grain sizes of the selected BCP ceramics are shown in Fig. 5.
Grain size decreased from 4.67 µm for the 25HA/75b-TCP ceramic to 3.17 for the 75HA/25b-TCP ceramic.
The grain sizes of the BCP ceramics decreased as the amount of HA increased.

The new parameters are Q'2h = Q2h / GBA; Q'2h(A) = Q / GBA(A); I'GBA = I /GBA; and I'GBA(A) = I / GBA(A) where Q2h is the charge accumulated during the test; I is the current density; the grain boundary area (GBA) is calculated as GBA = As[5.09544 x 10-3 exp(0.34696 G)] where As is the sample area in cm 2 and G is the ASTM grain size number; and GBA(A) is the grain boundary area actually covered by depletion zones.
These parameters incorporate the actual coverage of the grain boundaries with Cr depletion zones, are sensitive to Cr content within the 7.5 to 13.5% range across the depletion zone, and correlate with IGC and IGSCC tests for Cr19Ni10 steel.
Low temperature sensitization of Cr21Ni33TiAl (Alloy 800H), detected by double loop EPR, was related to chromium depletion at grain boundaries [76].
The unattacked chromium carbides are visible inside the attacked depleted regions at grain boundaries after the EPR test [44].
EPR offers a rapid response to the combined effects of a number of factors influencing the properties of materials, in addition to the depletion effect.

Of the large number of titanium alloys, Ti-6Al-4V titanium alloy has the best superplastic properties and good solid-state weldability.
Along with the known, existing advantages of the SPF/DB process, compared to conventional technologies, this method of producing light rigid hollow structures has a number of disadvantages.
The average grain size in VT6 Alloy is 1.2 microns; individual grains up to 4 microns in size are found.
The average grain size of the α-phase in bonded samples was 5 μm.
An increase in the bonding temperature to 900°C leads to a large number of grain size of α-phases to 9.1 μm.

Another approach to simulate the microstructure evolution is to directly consider the deformation of the grains in the metal by using crystal plasticity finite-element models [4].
Moreover, in comparison with the drawn wires, the strains increase with the number of passes.
Furthermore, the micrographs of the drawn wires, displayed in Fig. 6, show that the grains in the initial wire are strip-like shapes and the amount of the grains across the wire slightly increases with the number of passes.
To improve the accuracy of the prediction, future work may include more parameters such as grain size in the formulation of the hardness-strain reference curve.
However, the difference between the prediction and measurement of the hardness increases with the number of the drawing passes.

Copper minerals are fairly evenly distributed throughout the rock volume, sometimes forming individual grains with an average size of 0.07 and fine-grain aggregates 0.26 mm in size, sometimes up to 2.0-4.5 mm (Fig. 3).
The orientation of copper grains and aggregates is also marked, expressed quantitatively as the deviation of the longest axis of grains from the vertical in grades.
The void density, calculated as the ratio of the number of pores per unit volume of rock, is 9.10 mm-1.
According to the results of the research, it can be said that the rock strength decreases with the decrease in the parameters of the total and closed porosity, as well as the pore sphericity factor, and with the increase in the total number of closed pores and their density.
Quantifying mineral grain size distributions for process modelling using X-ray micro-tomography, Miner.

The difference of sub-granular (or small-granular) structure from the fragmentary one is that grains as a rule are limited by large-angle boundary (grain-boundary angle is more than 6 degrees), and the fragments differ with the small-angle boundaries (grain-boundary angle is less than 6 degrees) [8].
With the development of fragmentation the number of grains (fragments) is increased in the unit surface area, due to this the diffraction picture changes (consider that each fragment gives its reflection).
If it increases and the fragments are closer by their properties to micro-grains, micro-diffraction picture is closer to the circular one.
On the contrary if the grain-boundary angle remains small, micro-diffraction picture remains pointed containing one or few planes.
The reason for that phenomenon is that the boundaries of deformed origin absorb significant number of dislocations than boundaries of thermal origin do.

Some years ago, the single crystal analysis, developed by Ortner [2], was applied to coarse-grained materials (grain diameter larger than 300µm) [3,4]; it leads to the determination of the whole stress tensor over the grain.
Nevertheless, most of materials exhibit a small grain size (10-100µm) so that classical techniques can not be used to get local stresses.
With the Kossel technique, for most materials whose grain size is larger than 5µm, the diffraction concerns only one grain in the material so that a single crystal analysis can be performed.
For the same working distance, the number of intercepted cones varies between materials: more are observed on copper pattern than on the steels one.
A high number of Kossel curves is favorable for crystallographic orientation and unit cell parameter determinations.

Epitaxial growth means that the texture of the film is composed of only a small number of different orientations with fixed relations to the substrate.
Since the number of analyzed grains is limited there is a risk to miss some less frequent orientations. 3) Magnetic hysterersis loops in different sample directions: if the grains are oriented randomly the shape of the hysteresis loops does not depend on the direction in which it is measured. 410 However, if the easy axis of magnetization is aligned in the film plane, hysteresis loops and especially the remanence measured parallel and perpendicular to the film will be different.
The composition of the films was adjusted by varying the number of pulses on each target.
The grain size of Sm-Co is roughly the same as the film thickness.
The c-axis of the Sm-Co grain is tilted 60° out of the film plane.

The microstructure of rheo-diecasting tensile bar mainly consists of fine α1-Mg grains with an APD (average particle diameter) of about 32μm and relatively small α2-Mg grains with an APD of about 14μm.
The number of grains increases and the liquid content decreases in the microstructure form the side to the center.
Finally they grow to super refined grains less than 5μm in diameter.
When the rotation speed is 300r/min, the number of primary particles is increased and the number of dendrites is reduced.
It enhances the amount of grains and refines the microstructure.