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A decrease in the number of pores accompanied by an increase in density also causes an increase in microhardness.
Variation of wear rate with vol. fraction magnesium 3.5 Microstructure Investigation The mechanical properties of the composite will be coherent with the addition of the reinforcement particle number and particle size, as well as the microstructure image [22].
In Figure 24, the number of pores has decreased quite drastically compared to those formed at a sintering temperature 550℃.
The number of pores will decrease as the sintering temperature increases due to atomic diffusion.
Sundarraj, “Influence of Mg on grain refinement of near eutectic Al-Si alloys,” Metall.

The grain size of spherical CaCO3 became bigger, surface became smoother, and particle dispersion became better with the increase of calcium ion concentration.
The content of vaterite increased and particle grain size changed a little with the increase of pH.
The application of vaterite particles is determined by a great number of strictly defined parameters, such as large surface area, good dispersibility, small density, good solubility and so on[1-2].

For important compaction energies, exceeding the optimal one, the over-compaction can lead to the disintegration of grains and then the granular structure is not as resistant as the initial one.
In HEB 195 [14], the choice of the press depends on the desired pressure and the number of units produced per day.
Three specimens were prepared for each number of blows (25, 56, and 100 blows) (Table 4).
Using a scanning electron microscope (SEM), it is shown that the grains, after stabilization, form a honeycomb structure which is a result of the hydrates precipitation on the surface of the grains.
Table 8 shows the difference between the RE technique and PEB in terms of execution time, materials, and number of workers.

To improve the cement concrete deformation, small toughness traditional defects, with Adding the rubber grain in the concrete to form the rubber particles concrete; flexural modulus of Rubber particles of concrete and ordinary concrete was comparative studied, two kinds of concrete damping change was analyzed by using the finite element, through three point concrete trabecular bending test, the fatigue properties were comparative researched , the rutting test methods were used in proving the rubber particles of concrete of erosion performance; According to the test made the mechanical parameters of acquired in experiments , the applying the MEPDG 2002 design method, the road surface damage state were forecasted of the two kinds of concrete pavement in the design of the end; Experiment shows that rubber particles cement concrete flexural modulus is reduced by 12% than that of ordinary cement concrete, the damping ratio increased by 30%, the fatigue life have greatly improved, and surface
achieved initial success in the application of industrial and civil architecture, such as the use of shock absorption and sound insulation function in seismic foundation, the railway sleepers and sound barriers has wide application, but it is still in the research stage in the cement concrete pavement, the researches show that the good deformation property of scrap tire rubber particle in the cement concrete has the following significance: from engineering application view, rubber particles mixed in cement concrete materials to help improve the brittleness shortcomings, promote its absorbing heat insulation, sound absorption damping performance, impact resistance and crack resistance[1];From the economic point, strongly built rubber particles of cement concrete pavement, to break the high cost of asphalt pavement monopoly situation, can promote the development of local economy[2].From the section of environmental protection, rubber particles of cement concrete to be able to deal with a large number
Table 1 Flexural strength contrast between rubber particles concrete with normal concrete samples number failure load [kN] flexural strength [MPa] average flexural strength [MPa] normal concrete 1 22.8 5.81 5.64 2 22.4 5.71 3 21.2 5.41 rub-concrete 1 22.6 5.76 5.49 2 21.3 5.43 3 20.8 5.30 By bending test results indicate that two kind of mixture bending strength are satisfy the standard requirement (more than 5 MPa).
Table 3 Normal and rubber cement concrete fatigue properties contrast specimens name stress ratio stress level [MPa] load recycle number[N] logN normal-concrete 0.8 5.28 88 1.94 0.6 3.96 774 2.89 0.4 2.64 2732 3.44 rub-concrete (same stress ratio) 0.8 5.04 7843 3.89 0.6 3.78 8764 3.94 0.4 2.52 11356 4.06 rub-concrete (same stress level ) 0.83 5.28 304 2.48 0.62 3.96 4060 3.61 0.41 2.64 7893 3.90 Fig. 1 Normal and rub-concrete fatigue properties contrast Fig. 1 indicate that in the same stress than conditions, rub-concrete fatigue life is greater than normal cement concrete, with the improvement of the stress ratio, rub-concrete fatigue life is greater than that of normal concrete increased; In the same stress level, the two kinds of concrete are similar to the fatigue of the curve, the range of rub-concrete fatigue life increased basically the same under different stress level conditions.
Table 4 The structure experimental road pavement layer number thickness[m] layer name modulus of resilience[MPa] checking total stress[MPa] 1 0.30 normal concrete 42100 4.90 0.28 rub-concrete 37100 4.87 2 0.18 cement stabilized macadam 1800 - 3 0.30 lime and cement stabilized soil 1200 - 4 0 soil base 40 - Forecast Analysis Results.

Due to their superior thermomechanical performance and oxidation resistance at elevated temperatures, advanced silicon nitride ceramics with elongated reinforcing grains have been considered for hot-section components in advanced microturbines to achieve the stated goals.
Reported results are uncensored because fractography analysis was only conducted to identify strength-limiting flaws for limited number of samples via optical and scanning electronic microscopy.
As for the machined SN281 rotor hub samples the strength limiting flaw was associated with the very large elongated grains (~100-150 µm long and 10-15 µm diameter).
The presence of these large elongated grains is very typical for SN282 silicon nitride due to its high sintering temperature.

For example, number of the adhered cells to the nanorough surface with TiO2 nanotubes increases by 400% in comparison to microcrystalline Ti [8].
The nanocrystalline sinter, due to a large volume of the grain boundaries is easily etched and hence this specific morphology is obtained.
Depositing at –5 V (e) results in thicker coating composed of highly cracked HA grains.
The cracking leads to lamellar morphology, higher roughness and formation of lamellar form of the Ca–P grains.

Ottawa sand, consisting of rounded silica grains.
The bottom of the scratch seems tormented probably due to the nature of thermal spray coatings which has a lamellar grain structure.
The size and the flake-like aspect of the debris are probably due to the lamellar grain structure of the coating resulting from the rapid solidification of small powder particles, flattened by striking the substrate at high velocities.
The increase of the number of erodent particles results in an increase of the material removal rate.

In addition to layers high adhesion strength, a number of requirements are imposed on bimetallic brass-steel-brass strips in terms of dimensional accuracy, mechanical properties and microstructure [6].
Relative reduction during cladding affects bimetal layers adhesion strength, character of microstructure, the size of recrystallized grains, strip mechanical properties, and dimensional accuracy [7].
Large values ​​of joint deformation degree lead to excessive grain refinement after recrystallization process and increase material mechanical properties anisotropy, while lower values ​​contribute to excessive growth of ferrite grains during annealing and surface deterioration after stamping [8].

In addition, TiAl phase (g) undergoes significant grain growth, which in practice, impedes or even renders treatment impossible.
In order to improve the properties of TiAl phase (g) its alloys are usually added with three groups of elements improving plasticity (chromium, manganese and vanadium), high-temperature creep resistance and corrosion resistance (niobium, tantalum, tungsten and molybdenum) and those causing grain size reduction (boron, carbon, silicon, oxygen and lanthanides).
The samples for microscopic metallographic tests were subjected to grinding with abrasive paper designated 80, 320, 1000 and 2500, followed by polishing by means of polishing cloths with an addition of diamond and, next, corundum slurry with a grain size of 3 and 0.05 mm respectively.
The strength of the brazed joints made of alloy TiAl - g (TiAl48Cr2Nb2) is conditioned by the number of intermetallic phases precipitating during a brazing process.

In addition, there are no martensitic kinetic models containing initial austenite grain size effect.
Therefore, we made an empirical kinetic model including austenite grain size term for the martensitic transformation of AISI 5120 steel as a modified Zener-Hillert type formula [22,23]
( ) 0 1 0 1 2 1 G b b G a a G M M M dY Y Y dT α β × + × + × = ⋅ ⋅ − (6) where G indicates the ASTM grain size number and α, β, a0, a1, b0, and b1 optimization parameters.