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The microstructure of unreinforced VAL12 (fig.1a) shows dendritic morphology which gets refined and attains fine grain structure for hybrid composite with 6 wt% ZrO2, 1 wt% Gr.
When the percentage reinforcement of dispersoids in the matrix is increased, number of nucleation sites increases, reduces the time for dendrite growth, resulting in finer micro structure [5,8,9].
The grain size (ASTM E112) and porosity level (ASTM B276) measured using micro structural analysis through foundry plus analyzing software are presented in table 2.
While increasing the percentage of ZrO2 with 1% Gr, there is a considerable decrease in the grain size up to 6% of ZrO2 due to virtuous bonding between the matrix and dispersoids.
The microstructural examination reveals the influence of dispersoids on the composites grain size, their distribution and influence on the properties.

In a number of fusible metals and alloys has been registered AE in the course of fusion and crystallization [4, 5].
The effects occurring in liquid metal and connected with change of viscosity owing to increase of coordination number have been fixed.
Pb has the GTSK-Iattice which is characterized by the big number of sliding planes for dislocations.
In pure Sn it is formed large grains and quantity of interactions between grains it is insignificant, but energy of these interactions is considerable, that is caused by the plastic deformation which is passing on the twining mechanism.
Crystallization of technical Sn occurs on impurity and small grains are formed, according to their quantity increases and the number of AE signals increases.

It shows that the calculated grain size increased with increase in Pb concentration.
The peak at 31.30o can be attributed to (113) orientation for PbS2, where PDF Number: 20-596 tetragonal structure, and the small peaks at 30.04o and 43.08o due to (200) and (220) orientation for PbS (PDF Number: 65-2935 cubic structure).
Figure (7): Grain size evolution for (002) and (110) orientation as a function of Pb concentration The grain sizes increase with increasing the Pb concentration, we can relate that to increase of the strain and/or increase of the thickness of the films and consequently nanotubes long (decrease the width from 25 nm to 19 nm).
The increase of the optical gap (with dopant) [43] has been accompanied improvement in grain size (crystallinity) [37]. 4.
Crystallographic properties have been investigated by XRD pattern hexagonal phase, where the grain size increased with PbS concentrations.

The grain size was 0-1000µm with the highest number of grains with size between 40200µm.
The grain size distribution is shown in Fig. 1.
The A/F epoxy resin in combination with PAA epoxy hardener was filled by the expanded perlite waste with a grain size of 0-1000µm with the highest number of grains between 40-200µm (Fig.1).
This is probably due to very little number of epoxy resin bonding perlite grains at the highest used filling ratio.
With the increase of filling ratio, the number of pores visible under the microscope decreased, probably due to creation of a different shape and diameter of pores.

The crystal quality of (111) orientation MgZnO thin film is higher than (200) one because of the stronger horizontal migration of atoms on (111) surface under high temperature condition, the surface of (200) orientation MgZnO thin film is smoother than (111) orientation one because of lower vertical growth speed of (200) MgZnO grains.
The grain size of (200) orientation MgZnO thin film is much smaller than (111) one, the rms roughness is calculated to be 1.2nm and 4.5nm for the (200) and (111) orientation MgZnO thin film, respectively.
The vertical growth velocity of (111) grains has been reported to be bigger than (200) grains for cubic structure compound thin film, the vertical height of (111) grains is higher than (200) grains, so the surface smoothness of (111) orientation MgZnO thin film is rougher than (200) one.
From XRC and AFM results the average grains size of (111) orientation MgZnO is bigger than that of (200) one, because the migration of Zn atoms is much easier in (111) orientation MgZnO and (111) grain has much stronger attractive force to Zn atoms compared with (200) one, there are more Zn atoms located in MgZnO lattice in (111) MgZnO and less Zn atoms in smaller number of grain boundaries in (111) orientation MgZnO.
The surface of (200) orientation MgZnO thin film is smoother than (111) one due to smaller vertical growth rate of (200) grains. (111) orientation MgZnO thin film possess better crystal quality and higher solid solubility of Zn atoms in (111) lattice, so the band gap of (111) orientation MgZnO thin film is smaller and the UV light range of which could be expanded to longer wavelength direction.

A large number of piezoelectric sensors and devices are present in automotive, aerospace, aircraft and related industrial applications, often as vibration sensor or cancelling systems [1].
The grain size in the undoped BMT-PT specimen was about 1.5 μm, but grain size remarkable increased with the increasing amount of MnO2 addition in the doping range 0mol.% ≤ m ≤ 1.0 mol.%.
The specimen doped with 1.0 mol.% exhibited the largest grain size about 3.0 μm.
However, further increasing amount of MnO2 above 1.0 mol.% reduced the grain size gradually.
The increasing of grain size leads to the reducing of dielectric constant and loss too.

The experiment results investigated that the sample annealed with constant temperature of 300 has the high grain size and surface roughness.
Table1 Sample Number Annealing mode A Annealing with constant temperature B Annealing with temperature rising step by step C As-grown X-ray diffractometer (Cu Ka radiation with the wavelength of 0.15406 nm) was used to investigate the crystalline phase of the thin films.
This result indicates that the grain dimension increased after annealing.
Sample A, which was annealed under constant temperature of 300 for 2 hours, has the highest grain size.
The images indicate that the grains exhibit a circular shape for sample B and C.

Introduction Plastic deformation is characterized by tangled dislocations[1], dislocation pile-ups[2] at Grain boundaries, wide stacking faults and twins, resulting from the low stacking fault energy.
b a Fig.3 (a) The impedance change of austenite grain under different strain level; (b) The impedance change of austenite under different strain level at the frequency of 0.1Hz According to Fig.3 (a), austenitic grain impedance presented capacitive reactance characteristics.
With the increase of the deformation, the impedance of austenitic grain decreased monotonously.
(2) Consequently, surface potential changed with the number (n) of dislocation in a dislocation pile-up monotonously.
a b Fig.4 (a) Image of dislocation pile-ups in the grain boundary under the strain of 30%;(b) Image of martensite and cell wall under the strain of 40% Through the Fig. 4(a), plane dislocation pile-up was observed under the strain level of 30% on the grain boundary.

Influence of natural sands with diffierent maximum grain size and binder-aggregate ratio on the compressive strength of RPC has been determined experimentally at an age of 3,7 and 28 days.The results are plotted in Fig.1(a) and Fig.1(b) respectively.
From the experimental data shown in Fig.1(a), with the decreasing of the maxium grain size of natural sands,the water-binder ratio increases ,thus the density drops and then the strength.
RPC with natural sands removing impurities,with a maxium grain size of 4.75mm has no great diffrience from RPC with srandard sand.
From these results we can conclude that 100MPa RPC should result from the following composition: addition of 15% superfine slag powder,a binder-aggregate ratio of 1.2, natural sands with a maximum grain size of 4.75mm removing impurities.Especially, the fluidity of mortar controlled from 190 to 210mm is also necessary. 4.
Although water-binder ratio is very low, but still there are a number of redundant moisture .This is also reflected by the fluidity varied from 190 mm to 210mm.

When the true strain was 0.1, the martensite separated the β grain into a large number of micron-sized grains.
In order to obtain the structure of fully broken grains, the ingot was upsetted and stretched repeatedly in the two-phase region of (α+β) by 4500t fast forging machine.
Therefore, soft αp grains are more easily to undergo plastic deformation than that of hard βtrans phase during compressive deformation.
[11] Wei Chen, Qiaoyan Sun, Lin Xiao, Jun Sun, Deformation-Induced Grain Refinement and Amorphization in Ti-10V-2Fe-3Al Alloy, J.
Bhargava, Influence of β grain size on tensile behavior and ductile fracture toughness of titanium alloy Ti-10V-2Fe-3Al, J.