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And it is the reason of that high base number sulfonate showed good extreme pressure property.
Analysis methods (1) The mensuration method of total base number(TBN) is SH/T0251
Results and discussion Freeze-etching electron microscopy of the product The enlarged 100000 times freeze-etching electron microscopy of synthesized nano carbonate sodium was shown in Figure 1, its grain size analysis with Zetaplus/90 plus type zeta laser particle size analyzer was shown in Figure 2.
Figure 7 The SEM results of worn surface, 5Cst (left) and 1.0wt% SSSU (right) From figure 7, the SEM micrographs indicate that severe scuffing occurs with lubrication of base oil alone, taking on grain abrasion characteristic.
The tribogical reaction between metals can produce partial high temperature, and it made carbonate releasing from high base number sulfonate, the inorganic carbonate sodium reacted with iron oxide and fresh iron in metal surface to generate oxide sodium and ferrite sodium, to form protective film in metal surface, so it is the reason that the high base number alkali sulfonate has a certain tribological performance.

As for MA method, it is possible to fabricate precise parts with very fine grained microstructure.
Inevitable problems might be raised such as coursing of grain size and thermal strain after relatively long heat treatment.
observed after Fig.5 Sharpy impact test results of HNS (23%Cr-4%Ni-2%Mor-1%N) � �� �� �� �� ��� � ��� � ��� � ��� ��� ��� 7HPSHUDWXUH 
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of count, c/s N 1S As polished Corroded area Non-corroded area under crevice NO NH3 Nitride N in alloy 23%Cr23%Cr23%Cr23%Cr----4%Ni4%Ni4%Ni4%Ni----1%N1%N1%N1%N 700 600 500 400 300 200 100 0 408 406 404 402 400 398 396 394 Binding energy, eV Numbers of count, c/s N 1S As polished Corroded area Non-corroded area under crevice NO NH3 Nitride N in alloy 23%Cr23%Cr23%Cr23%Cr----4%Ni4%Ni4%Ni4%Ni----1%N1%N1%N1%N 700 600 500 400 300 200 100 0 408 406 404 402 400 398 396 394 Binding energy, eV Numbers of count, c/s N 1S As polished Corroded area Non-corroded area under crevice NO NH3 Nitride N in alloy 23%Cr23%Cr23%Cr23%Cr----4%Ni4%Ni4%Ni4%Ni----1%N1%N1%N1%N 700 600 500 400 300 200 100 0 408 406 404 402 400 398 396 394 Binding energy, eV Numbers of count, c/s N 1S As polished Corroded area Non-corroded area under

The basic value is the number of AE events per a period of time.
This parameter is a simple indicator for determining the degree of damage to a material, where generally applies that a larger number of AE events indicates a higher degree of material damage.
Fig. 2 The number of AE events during the static modulus of elasticity test, the vertical axis shows logarithmic scale.
Kalina, Effect of the by-pass cement-kiln dust and fluidized-bed-combustion fly ash on the properties of fine-grained alkali-activated slag-based composites, Mater.
Karel, Shrinkage of Fine-Grained Composites Based on Alkali- Activated Slag, Non-traditional Cement & Concrete, Brno, 2017, 20-21

In this paper, the isothermal solidification dendrite growth model coupling the forced flow-field for binary alloy was established, calculating the phase field and solute field equations by the finite difference method; the flow field equations were calculated by Sola algorithm; in order to save calculation time, reduce the computational volume, double grid method was adapted to calculate the phase field, solute field equations and flow field equations, respectively; take Al-Cu binary alloy for example, the simulation results can capture the interactions of the liquid metal flow and multiple grains dendrite growth under forced convection environment.
In this article, the binary alloy multi-grains dendrite growth isothermal phase-field model which Feng Li et al [12] proposed was coupled with the flow field, the phase-field equation can be expressed as equation (1): (1) Where, M is solid interface migration rate, Φ is phase field order parameter, t is time variable, ε(θi) is a parameter associated with the interfacial energy, fΦ represents the first derivative of free energy density on the phase-field order parameter, and its representation form is as equation (2): (2) Where, R is gas constant, T is temperature, Vm is molar volume, h(Φ) is potential function, W is phase field parameter, g(Φ) is residual free energy function, c represents the concentration of solute in the alloy, the subscript L, S represents for liquid and solid phase respectively, the superscript e represents equilibrium state.
Correspond to the x and y axis (the horizontal direction is x) in coordinate system, the computational grid number of phase field and solute field both are 1200×1200, the grid size is 1 × 10-8m (Δx = 1 × 10-8m ), set the initial nucleus as the ball with the grids number radius R=10.
Because of different thickness of the grids, resulting in different space and time accuracy of flow field, phase field and solute field numerical solutions within the calculation region, for this reason, space factor Nw and time factor Nt were introduced, ， (10) (11) (12) (13) (14) (15) Where, V represents the flow velocity, the subscript f indicates the numerical solution of the calculated flow field grid, I, J, T and i, j, t represents the space and time node in different grids, respectively, in formula (12), (13), n is a natural number less than Nw, in formula (15), n is a natural number less than Nt.

The samples had a sufficient color inhomogeneity up to strains of e = 6.0-6.5 corresponding to the number of revolutions of n £5.
On the basis of these data we can conclude that the original metal powder mixture has been suffering the number of structural and phase transformations determined by the strain during severe plastic deformation up to solid solution formation at room temperature.
Attempts to determine the concentration and the role of point defects, usually vacancies in mass transfer during plastic deformation have been undertaken in a number of computational works [10–12].
According to earlier research on a number of pure metals [5-7], decreasing of the deformation temperature blocks thermally activated processes necessary for a non-conservative motion of dislocations.
Dheda, On the minimum grain size obtainable by high-pressure torsion, Materials Science & Engineering A. 558 (2012) 59–63

Intermetallidshaving a number of advantages are considered to be promising materials for metal matrix.
Such methods include using a number of other CEF sources such as laser, ion-plasma, explosion,etc.
In the structure of the brittle-ductile fracture, a little number of small pores(with a size of 0.2 to 0.5 mm), uniformly distributed over the metal of the ingot, were found.
A significant grain refinement in the ingot is occurred with an increase of the Zr concentration and addition of C (Figure 1, d).
The rest of the structural components of the alloys are located along the grain boundaries.

No difference in grain structures among the three different planes was observed.
The average grain size was about 20μm.
It should be noticed that the basal planes, on which slip is easy to occur, for the 45-degree and transverse specimens are oriented at 45゜and normal to the loading direction. 103 104 105 106 107 108 40 60 80 100 120 140 Number of cycles to failure, N f (cycles) Stress amplitude, σa (MPa) Longitudinal Transverse 45-degree Longitudinal Transverse 45-degree Interrupted tests Table 2 Tensile properties of AZ61.
The relationship between the crack length and number of cycles normalized by the fatigue life is shown in Fig. 7.
Therefore, it is suggested that the longitudinal specimen has less number of slip systems and consequently indicates higher fatigue limit compared to the 45-degree and transverse specimens.

Since the coarse (larger than 1 µm) IM particles provide sites for crack initiation, the lower toughness and resistance to propagation of fatigue cracks are related to their size and larger number in the matrix.
Because the limits to reduction of these impurities are set of cost, many commercially available 7xxx alloys contain significant amounts of Fe and Si, which react with Al and alloying elements to form a large number of IM phases [1,2].
The plots of crack length, a, vs. number of cycles, N, were made and average crack growth rates, da/dN, were computed.
The EDS analysis in TEM confirmed that both small precipitates in the former dendrite interiors of the cast structure and relatively coarse precipitates at the grain boundaries were those of the η-MgZn2 phase, Fig. 1c.
A general view of the fractured specimen surface illustrated in Fig. 3 shows that in the other alloys microcracks are initiated more readily than in the alloy 1 because of the higher number of larger particles.

The MZ 1 specimen composed of YSZ 1 powder is characterized by the TC defect structure with large numbers of micropores and microcracks, while MZ 2 specimen with YSZ 2 powder contains only a few microdefects and is fairly densified as compared with the other TBC systems.
the same TC powder as MZ 2, on the contrary, a number of the macrocracks have already extended or penetrated through major part of the TC over the length of 100µm vertical to the TC / BC interface.
The 240~400 numbers of microphotographs per one specimen were taken until completing the test.
It was confirmed that the initiation site of TC spalling should coincide with the region subjected to the more extensive plastic deformation in the alloy substrate for all the specimens tested, of which magnitude is probably different depending on the crystallographic orientation for each grain.
Such a deformation might depend strongly on the relative crystallographic orientation to the loading axis of individual grains with relatively large size in the alloy substrate.

According to a dispersion relationship of the helicon wave, the electron density is proportional to magnetic field if the parallel wave number is fixed.
The Hiden probe measures the electron and ion currents to provide electron and ion number density measurements [18].
The probe has an error of ±50% for electron and ion number densities and ±20%for electron temperature [19].
Fig. 5(a) shows there are a large number of small dots adsorbed on the surface of big grain.
Compared to Fig.5 (a), the average grain size decreases with the increasing RF power.