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The filler of the composites was brick crumb with a grain size of 1 to 4 mm, the ratio of the dose of filler to brick dust was 1.05.
The grain size of the precursor practically did not affect the toughness and only slightly the fracture energy (differences of values were up to 12%).
Larger grains form a binder phase of alkali-activated aluminosilicates on their surface, but some of the grains, depending on their size, remain in their original form.
This maximized the number of determined parameters from a given number of fracture tests.
Keršner, A neural network ensemble for the identification of mechanical fracture parameters of fine-grained brittle matrix composites.

Fig. 3 shows the SEM images of YSZ grains at 5,000 magnification.
With the addition of 0.5 mol% Nb, the number of small (<1 µm) grains increase, with decreasing irregularity, forming more spherical grains.
The size and number of bulk crystal decrease with increasing Nb mol%, until 1.0% mol. 1.5% mol exhibits surface morphology similar to the undoped sample.
This can be explained by the preferential segregation of Y2O3, which will repulse Nb ions away from the YSZ grain boundary [10].
Mayo, The effect of grain size, porosity and yttria content on the thermal conductivity of nanocrystalline zirconia, Scripta Mater. 39 (1998)1119-1125

Mechanical properties directly depends on grain size of the particles.
So controlling the above parameters plays a vital role in grain refinement.
The ball mill consists number of ceramics balls.
The grains are not densely packed.
As the properties of the specimen mainly depends on its grain size, fine grains helps in attaining good mechanical property.

Ultrasonic treatment in the molten magnesium alloy would refine the grains, increase homogeneity, reduce segregation and degas the gas in the alloy [10-13].
The results indicate that the ultrasonic treatment can refine the grains, degas the gas involved in the alloy and decrease the segregation of the AZ91 alloy.
And because of the high pressure pulses caused by the ultrasonic cavitation, the wettablity of large numbers of impurity particles, such as Mn and Fe based intermetallic particles, will be improved by eliminating the gas absorbed on the particles and fill the melt in the micro cracks of the particles.
And the grain nuclei generated by the two methods will be distributed to the molten alloy by the acoustic streaming induced by the ultrasonic vibration.
So the grains of alloy will be refined, as shown in Fig.2 (c).

The metallurgy behind cryogenic processing of high-carbon steel is that it creates a large amount of fine or small carbides that precipitate uniformly throughout the lattice structure, resulting in close and fine grain structures[1, 2].
Hence the deep cryogenic treatment with a larger soaking time would bring out an enhancement in mechanical properties due to austenitic transformation as well as grain refinement.
Table 1: Chemical Composition of Base Metal and Weld Metal Major Composition C Mn Si P S Cr Mo BM (ASTM SA-387 Grade 11 Class II) 0.162 0.614 0.612 0.009 0.009 1.36 0.606 WM (E8018-B2L) 0.07 0.75 0.5 0.025 0.02 1.3 0.5 Table 2: Welding Process Parameters Welding Process SMAW Parent Metal 1.25Cr - 0.5Mo steel Electrode Specification E 8018 – B2L Electrode Size Diameter 3.15 mm Preheat Temperature 200°C Inter pass temperature 200°C Root run current 70 A Filling current 140 A Voltage 20-24 V Final run current 75-80 A Number of passes 5 Cryogenic Treatment (CT).
Cylinder Chamber Controller Figure 1: Cryogenic treatment system Figure 2: Cryogenic treatment cycle 100mm (a) F P 100mm F P (b) Figure 3: Microstructure of base metal (a) As-received, (b) Cryogenically treated (F-Ferrite, P- Pearlite) AF AC PGBF 100mm AF 100mm PF (b) (a) Figure 4: Microstructure of weld metal (a) As welded weldment (b) PWCT (PGBF-Polygonal Grain Boundary Ferrite, AF-Acicular Ferrite) In the weld metal region shown in Fig. 4, the microstructure observed contains generally grain boundary ferrite in addition to acicular ferrite regions in both the conditions.
The HAZ is further categorised as coarse grained HAZ and fine grained HAZ as the grains are more coarsened in CGHAZ and refined in the FGHAZ.

The degradation is strongly influenced by: (a) the content of additives, (b) the grain size, (c) the temperature, (d) water vapor enhances the transformation and (e) the partial water vapor pressure.
Table 1 Starting materials Serial number CP(wt%) Al2O3(wt%) (a) 85 15 (b) 90 10 (c) 92 8 (d) 94 6 (e) 100 -- The surface phases were identified by X-ray diffraction analysis (XRD) using Cu-radiation before and after ageing treatment.
Firstly, the fracture microstructure is shown in Fig. 3, from which it is to be noted that the grains of Al2O3 grew up after ageing treatment (the bigger flaky grains are Al2O3 grains).
The extraction of the Al2O3 grains can also be obviously observed in the images.
The dispersion of the Al2O3 particles and the growth of the Al2O3 grains during ageing can certainly impede the transformation of tetragonal to monoclinic phase. 2.

The presence of a hydrostatic pressure as a general feature of SPD methods is essential for achieving the high strains and the introduction of the high amount of lattice defects, which are necessary to establish new grain boundaries.
The latter are highly considered to carry plastic mechanism especially when the grain size gets down to a critical limit (several tens of nanometer) depending on material and deformation temperature (twinning) [10].
These models are directly based on essential physical parameters like the number of dislocations, an outer cut-off radius describing the extension of the strain field of dislocations and a dislocation contrast in analogy to transmission electron microscopy.
The question where the deformation induced defects recombine/annihilate (surface, grain boundary, etc.) and how they contribute to the formation of non-equilibrium boundaries is a major task in future investigations.
This is a hint that the extent of the grain fragmentation is completed under pressure whereas the microstructure changes upon unloading by mechanisms of recrystallisation and recovery [26].

The average particle size and the average grain size of the ceramics were increased with the increase of calcination and sintering temperatures.
The diffraction lines were indexed on the basis of a cubic structure matched with JCPDS file number 030632.
The average grain sizes of the BSZT ceramics increased from 0.88 to 2.60 µm when the sintering temperatures increased from 1400 to 1600 o C as shown in Table 2.
The lattice parameter a, density, shrinkage, average grain size and dielectric constant at room temperature of BSZT ceramics CO/CLUSIO/S (Ba0.25Sr0.75)(Zr0.75Ti0.25)O3 powders can be obtained from a solid-state reaction method.
e-mail: researchcmu@yahoo.com Fax: +6655-963-501 Sintered temperature ( o C) Lattice parameter a (Å) Density (g/ cm3) Shrinkage (%) Average grain size (µm) Dielectric constant (εr) 1400 4.0811 5.38 5.13 0.88 59 1450 4.0811 5.39 5.49 1.24 65 1500 4.0785 5.41 10.39 1.45 79 1550 4.0759 5.42 16.95 1.64 93 1600 4.0682 5.41 17.68 2.60 79

Results show that the coefficient of variation increases as the size of the probe reaches the size of the particle while a very large ratio of probe size to grain size would decrease the detectability of local soil variations due to averaging effects and smoothening.
The large and small probes are gradually inserted into 10 specimens prepared with different grain sizes by the water pluviation method to attain the most homogeneous soils possible (tap water, ρfluid = 23kΩ cm).
Note: 0* during specimen preparation. 1 10 100 0.1 1 10 100 Ratio (dprobe/D50) COV of resistance [%] Large probe (Needle #2) Small probe (Needle #3) Grain aliasing - Local average Grain detection 0.01 0.1 1 10 100 0.01 0.1 1 10 Resistivity ρρρρ [KΩΩΩΩ cm] Resistance R [KΩΩΩΩ ] Large probe Small probe Small probe R = α2 ρ where α2 = 6.7 [cm -1] Large probe R = α1 ρ where α1 = 2.15 [cm -1] Resistivity ρρρρ [kΩΩΩΩ cm] Resistance R [kΩΩΩΩ] 0 20 40 60 80 100 120 140 160 180 200 7 8 9 10 11 12 Resistance [kΩ] Depth from water surface [mm] (a) 0 20 40 60 80 100 120 140 160 180 200 7 8 9 10 11 12 Resistance [kΩ] Depth from soil surface [mm] (b) Saturated Drained 0 0* 128 0: Before impact 8: Impact No.8 128: Impact No.128 0: No drainage 0*: Initial drainage 128: Impact No.128 0 8 128 Liquefaction Monitoring.
The electrical resistivity increases with the number of impacts due to the decrease in porosity.

A large number of inclusion defects were found during the metal supervision process of 15Cr1Mo1V steel main steam pipeline of the Russian-made thermal power unit.
There are a large number of inclusion defects in the three sets of samples.
The metallographic examination results of ①②③ samples show that the metallographic structure of sample① is bainite + ferrite + carbide particles, aging grade 3, and grain size 6～7.
The metallographic structure of sample③ is ferrite + carbide particles, and the carbides are precipitated in the local grain boundary, aging grade 4 and grain size is 5～6.
The number of stress cycles of the unit within 105 hours was 82.