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Many authors reported that this technology offers different combined advantages such as degassing, grain refinement and eutectic Si and Fe-rich compounds modification in aluminum casting alloys [8-11].
Titanium is more widely used than steel as it appears to dissolve more slowly and, when dissolved, it can act as grain refiner [18].
It has to be reminded that the micrographs refer to gravity cast samples; a real semisolid process is characterized by the injection of the alloy into a die, which produces high shear stresses in the slurry, strongly affecting its viscosity and enhancing the formation of a high number of globules with round shape.
The SEM-EDS analyses of the obtained samples clearly show the presence of a high number of Fe-rich intermetallic compounds (Fig. 6) as a consequence of the enrichment of the alloy in Fe, Mn and Cr content due to the dissolution of the horn (Alx(Fe,Mn,Cr)ySiz [26]).

The samples selection was carried out randomly, and the number of samples (21) is sufficient and selected in accordance with the applicable rules for the performance of the said structural analysis.
The tested samples include in a ferrite and pearlite grain, where the corrosion pits occur (Fig.7 – point 1-5, chemical composition Table 1 – 2 point 1-5, exemplary samples), numerous non-metallic inclusions, which is a material defect.
Causes of pitting corrosion in the tested boiler Causes and spots where the pitting corrosion occur may be [5]: - jogs (dislocations) caused by stresses (mechanical, thermal), - spots of, other than average, chemical composition caused by segregation, non-metallic inclusions or precipitates, - grain boundary, - mechanical damage spots.
Summary The main conclusions regarding the tests performed may include: - pitting corrosion of the heat exchange surfaces of the tested boiler characterized with high intensity and short time of progress, - the depth of pits equaled even up to 50% of the pipe wall and boiler plates’ thickness, - pits were located only in several spots on the heat exchange surface (5 pits in the furnace cover – Fig.1,3 pits in upper part of the oil-combustion pipe – Fig.2, 6 pits in the smoke tubes), - the quality of the steel used for the construction of the boiler should be determined as low due to a number of inclusions occurred during the steel deoxidation process

We can see that the nanodefects density, namely the number of nanodefects per unit of MWCNT surface area increases with the increasing treatment time.
Hereafter, the number of nanodefects per unit of the MWCNT surface area is referred to as the nanodefect density.
Figures 4(a) and 4(b) show the microstructure of the fracture surface of the 1.9 vol.% pristine and 1.9 vol.% acid-treated MWCNT/alumina composite, respectively From Figs. 4(a) and 4(b), the shape of alumina grains were clearly observed from the fracture surface, indicating that the fracture of both the composites occurred along the grain boundaries, that is, intergranular fracture mode.

Taking into account that the diffusion rate of titanium and copper atoms in molten aluminum is several orders of magnitude higher than the diffusion rate in the solid phase of aluminum, the following irradiation modes have been chosen for treatment of the “film (Ti or Cu) / (Al) substrate” system: t = 50 μs; ES = (10, 15, and 20) J/cm2; number of pulses N = 3, pulse repetition rate is 0.3 s-1.
The “film/substrate” system, formed by deposition of a metal film using the vacuum-arc method with evaporation of a cathode, is characterized, as a rule, by the presence of a large number of microdroplets (Fig. 1a).
The grain size varies from 0.5 μm to 7 μm.
Particles of the second phase (aluminides of titanium) are found in the bulk of the grains.

Block samples have been numbered respectively BS4-1, BS4-2.
Sample numbers is 4-1-2 4-1-1, respectively.
So just exerted a load, even if the small load, its variation will reach maximum and make granules close-grained.
The structure is destroyed, behavior between grains close to reconstituted clays, compression index diminishes quickly, around 225kPa later gradually slow, and curves tend to be remolded soil curves, as shown in the e-lgp until compress curve last superposition.

Experimental materials and methods Al-Si alloy is used as the experimental specimen and its compositions are listed in table 1.In the experiment, phosphorus modifier was utilized to conduct modification on the specimens and the primary silicon grains in tissues were refined using squeezing casting technique.
Large number of voids existed in the coating, among them, some of voids go through the interface between the coating and substrate.
In comparison with wrought aluminum alloy[11],the MAO coating of Al-Si alloy were looser, which was due to the large quantities of the primary silicon grains contained in the substrate of aluminum alloy.
There were the mullite phase with many diffraction peaks and small number of quartz (SiO2).

Prepare a number of extruded AZ31 magnesium alloy samples with the size of 80mm × 10mm × 3mm, and remove oxide film and oil on the sample surface.
Also, a little coarse-grained and lots of α-Mg that were prominent and extended to the base material (Figure 1) were observed in the heat-affected zone.
（a） （b） Fig. 3 The morphology of weld seam zone (a:α-Mg phase; b:eutectic structure) Scanning electron microscopy analysis showed that there were some long sliding steps in the fracture of welded joints, belonging to quasi-cleavage fracture, and the fracture had the characteristics of plastic fracture, reflecting that a large number of dimples in the roots of the slip steps and the necking phenomenon(Figure 4).
Because there were a large number of α-Mg, cracks were not easy to extend along the original path.

Conventional WC-Co coatings usually contain 70-95 wt% WC, with grain sizes ranging of 1-30 µm.
Journal Title and Volume Number (to be inserted by the publisher) 30 40 50 60 70 80 90 Angel (2 theta) -10 WC W2C W Co3W3C or Co6W6C (a) (b) (c) 30 40 50 60 70 80 90 Angel (2 theta) -10 WC W2C W Co3W3C or Co6W6C 30 40 50 60 70 80 90 Angel (2 theta) -10 WC W2C W Co3W3C or Co6W6C WC W2C W Co3W3C or Co6W6C (a) (b) (c) Figure 3.
Both coatings contained a number of newly formed phases.
was highly elongated in the direction of parallel to the substrate surface, and contained a very small number of carbides.

Dislocation, grain boundary and subboundary are pinned by the second phase particles, so the strength of the composite is enhanced while the excellent electrical conductivity of copper-matrix is retained.
(1) Where T is the temperature, ΔGT is the standard free enthalpy of reaction, n is the molar number, i and j are ordinal numbers, R and P mean the reactants and products.
A small number of stripe twin crystals can be seen in Fig.3 (a).

Table1 Haydite Grain size(mm) 1h bibulous water Cylinder pressure strength(MPa) Coefficient of softness Packing density (kg/m3) 5--20 8% 6.0 80% 740 Concrete Design.
Table 2 Concrete Design ( kg/m³) Number Light-weight Aggregate Water-cement ratio Cement Water Sands Shale Gravel A 0% 0.35 450 133 875 0 1125 B 25% 0.5 450 215 875 150 844 C 50% 0.3 450 130 875 300 563 D 62.5% 0.45 450 202 875 375 422 E 75% 0.25 450 122 875 450 281 F 100% 0.4 450 204 875 600 0 Results and analysis.
Table 3 The Test Results Number A B C D E F Ｅ7 ( 104 MPa ) 2.98 2.11 2.90 2.05 2.63 1.81 Ｅ14 ( 104 MPa ) 3.12 2.36 3.17 2.23 2.91 2.14 Ｅ28 ( 104 MPa ) 3.40 2.64 3.26 2.47 3.06 2.33 fcu,7 (MPa ) 53.4 35.6 48.8 37.0 45.1 33.4 fcu,14 (MPa ) 56.4 42.4 53.8 42.0 50.4 40.8 fcu,28 (MPa ) 61.5 47.5 56.5 45.5 52.5 44.5 density (kg/m3 ) 2450 2319 2188 2122 2056 1925 The Elasticity Modulus.
Table 7 Measured Value and Calculated Value of Elasticity Modulus(104 MPa) Number A B C D E F Measured Value 3.40 2.64 3.26 2.47 3.06 2.33 Calculated Value by Eq.1 3.59 3.41 3.55 3.37 3.49 3.30 Calculated Value by Eq.2 3.83 3.23 3.32 2.89 3.01 2.55 Calculated Value by Eq.3 3.52 2.94 2.96 2.52 2.58 2.22 From Table 7 , calculated value by equation 3 and measured value is in a good agreement, So the Eq.3 is suggest to calculating the elasticity modulus of combined concrete, namely Eq.4 (4) Conclusions For the combined aggregate concrete, the cube compressive strength, elastic modulus and apparent density decreases with the increasing aggregate lightweight aggregate volume fraction and water cement ratio, and they show linear relationships.