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Fixed gelled material total amount for 370 Kg/m3, sand rate 44% constant, change water-binder ratio of 0.35, 0.45 and 0.55, the aggregate limiting grain size is less than 26.5 mm, The slump for 160±20mm by cement materials control, different proportion (0, 40%, 50%, 60% and 70%) FASG composite powder to selected and the mixed quantity of proportion (FA: SG = 1:4) isometric substitute cement concrete C40 preparation, hope to achieve good workability and uniformity , Meet the rules about C40 intensity level requirements and and to mix C40 preparation high performance concrete, see table 3 and table 4.
Kg/cm3 Serial number C FASG W/B S G Water reducing agent /% B0 370 0 0.45 810 1030 1 B7 111 259 0.45 810 1030 1 Erosion simulation test.
At present, a large number of the theoretical and experimental research about the carbonization of concrete have been carried out by the experts and scholars being at home and abroad, the conclusion was same in principle, which concrete neuter problems, which is caused by the carbonation, acid rain contribution is not serious.
Concrete samples were cured for 28d on the standard curing (ST0), and sampling at ST1, ST3, ST6 mode (where, 0, 1, 3and 6 represent cycle number), there are 8 samples in all, four specimens are C40 high performance concrete and the other four are benchmark concrete, after surface treatment, microscope were observed by electron microscope, which were shown in figure 2, figure 3.
The interfacial Ca(OH)2 grain got smaller, which improved the microstructure of the cement base material, at the same time, due to micro aggregate effect of fly ash and slag, clearance of cement particle was filled, structure was improved, the aperture size and porosity reduced.

In the semi-solid forming process, aluminum is stirred from its molten state while decreasing the temperature to create semi-solid slurry with a controlled grain size, which is then injected into a die and formed with a press.
Semi-solid slurry with fine and globular primary particles was fabricated by using an electromagnetic stirrer (EMS) that controls grains size of A356 alloy.
For slurry without stirring it can be confirmed that a large number of rosette particles and a few fine-globular particle are distributed (Fig. 6 (b)).
But a large number of primary α-Al particles over 100 μm can also be seen, and the gap between primary α-Al particles is large due to a smaller number of primary α-Al particles.
This indicates that the less the number of primary α-Al particles in microstructure is the lower the elongation becomes.

Comparison of the microstructure from sample 1 to 4, it indicates cryogenic treatment had certain influence on the metallurgical structure, such as grain size of acicular martensite and carbides, content of residual austenite.
In the matrix of martensite, the number of primary carbides have decreased greatly in sample 3 which using shallow cryogenic treatment (-70℃) and tempered treatment (SCT) in one time.
The number of secondary carbides increased and their distribution was more homogeneously as shown in Fig. 1 (4), these was obtained after cryogenic treatment and tempered treatment in two times.
A number of key factors contribute to these results including: slender needle-shaped martensite which is obtained by quench, cryogenic and temper treatment has high hardness, and it also has better abrasion resistance.
Cryogenic treatment had positive influence on the metallurgical structure, such as grain size of acicular martensite and carbides, content of residual austenite, macrohardness of material and abrasion resistance. 2.

Low working temperature of the fluid cylinder (lower than the brittle transition temperature), the coarse grain size of the fluid cylinder material and the extreme stress cycle can all lead to cleavage fracture.
Fig. 3(3) shows the crack source region of the crack B, a large number of fatigue strip morphology can been seen in the left portion of the figure, and the fatigue strips distribute in dissimilar heights and direction due to the presence of the second phase particles.
Elements V could refine the grain to strengthen the toughness; Mn and Si have solid solution strengthening effects to the ferrite in addition to strengthen of the material; Mo, Ni, Cu and P can improve the ability of corrosion resistance.
Table 2 Tensile test date Material Test Number Elongation [%] Reduction [%] Yield strength [MPa] Ultimate tension [KN] Tensile strength [MPa] E4330 1# 17.2 56.8 984.4 132.9 1065.4 2# 15.8 57.9 965.2 126.9 1043.2 3# 15.8 57.8 978.9 131.9 1063.9 Average 16.3 57.5 976.2 130.6 1057.5 The stress levels distribution was preliminary designed as table 3.
Table 3 Fatigue test stress levels Design Stress σa [MPa] Stress ratio σa/σb Test Number 634 -1 0.5995 1 621 -1 0.5872 2 608 -1 0.5749 3 595 -1 0.5626 4 582 -1 0.5504 5 569 -1 0.5381 6 556 -1 0.5258 7 543 -1 0.5135 8 529 -1 0.5002 9 Bending Fatigue Test.

(2) The cutting tool selected is a diamond coated multi-point grinding tools with a grain size about 150 Grit according to ANSI (or P150 according to FEPA) [6].
Each abrasive grain corresponding to a cutting point has rake angle cutting edge γ < 0, so we can convert the abrasive particle diameter 2r ~ 100 μm and roughness height Rtmax approximately as shown in Fig. 4b and c.
The mode number is 10 and the range for searching the mode frequency is from 35 to 45 kHz.
The modified parameters are the number of slits and width.
Acknowledgement The research is funded by the Vietnam National University, Ho Chi Minh City (VNU-HCM) under grant number C2020-20-05”.

Therefore, it will form Kekendaer effect [13], leading to form a large number of pores on the surface layer and an uneven workpiece surface.
Furthermore, a large number of rare earth elements are adsorbed on the aluminized coating surface, and the corresponding activity aluminum atoms concentration decreases, where the diffusion of chemical potential of aluminum atoms greatly weakens, leading to the decrease of aluminized coating thickness and the defect of non-uniform aluminized coating thickness.
During the high-temperature oxidation process, with the number of cycles increased and time extended, the linear the cavity bands in the aluminized coating/substrate interface of the aluminized sample without added Y2O3 gradually gathered into linear cracks parallel with the surface.
At the same time, the microstructure of aluminized coating added rare earth Y2O3 presents smaller grains, due to grain refinement, increasing the aluminizing channel and slightly higher aluminum content in the aluminized coating, which not only increases the strength and hardness, but also improve the plastic, better resistance to cracking and spalling.
However, the aluminized coating of the sample prepared in high Y2O3 content (6% Y2O3) presents loose, and forms a large number of cavities on the surface, leading to an uneven surface of the workpiece.

The number of reports [1]~[8]on TBC has recently increased with attention to TBC.
A- A tm tc w t 45 R10 R30 A A 8.5 Fig. 2 Specimen geometry 50 100 150 200 250 300 350 400 450 500 1.0E+03 1.0E+04 1.0E+05 1.0E+06 1.0E+07 Nf　[cycle] Stress Amplitude : S [MPa] HIP Specimen HIP Specimen HIP Specimen HIP Specimen ● IN738LC ▲ IN738LC+NiCoCrAlY+Porous YSZ ◆ IN738LC+NiCoCrAlY+Dense YSZ ■ IN738LC+NiCoCrAlY NON HIP Specimen NON HIP Specimen NON HIP Specimen NON HIP Specimen ○ IN738LC △ IN738LC+NiCoCrAlY+Porous YSZ ◇ IN738LC+NiCoCrAlY+Dense YSZ Fig.3 Number of cycle to failure : N [cycle] Fig.4 shows the photos of fracture process.
The crack propagates intergranualarly first, and then finally it fractured at grain boundary because of cross section reduction.
The crack initiates from the surface corner and propagate intergranularly and finally fractured at the grain boundary.
Considering small number of data in their experiment, there is a possibility of micro-shrinkage effect.

The investigations and modeling of crystalline structures of oxides and their physical properties stand out in this direction, which are closely connected with the detailed study of microstructures at the molecular level: differentiation between surface and bulk effects given the grain sizes and boundaries, determination of conditions of the evolution and stabilization of a crystalline structure at different scale levels of the structural organization [1-3].
Step 2.To one of those ions (to what ion it is selected in a random manner), the third is attached, and so forth up to a predetermined number of built clusters; and a defined cluster must not overlap any previous one.
The density is computed as the ratio of the current number of ions N in a cluster to the volume of a sphere circumscribed about a system from its center of mass: ρ=N43πR3-1, (3) where R is the distance from the cluster’s center to the most distant atom.
The first parameter–the vertex-connectivity–shows the number of clusters having a common vertex with the initial cluster (l1), the second parameter–the edge-connectivity–the number of clusters having a common edge with the initial cluster (l2).
Numerical simulation of Al2O3 crystalline structures allows controlling the structures on multiple length scales and creating brand new materials with an ultrafine-grained structure as well as materials with unique properties and heightened operational characteristics [11-14].

Abstract: In order to study the explosion characteristics of nanometer aluminum, comparative experimental studies on explosion characteristics of nanometer aluminum powder and common aluminum powder with different grain diameters have been carried out by using the horizontal pipeline explosive test device.
With the industrial production environment et al part, especially the connectivity workshop environment which is using the long pipe to simulate the production and storage, it is hoped to prevent accidents of aluminum powder. 1 Pipe explosive device test system In this paper, it is used aluminum powder of both 100 nm and 75μm grain diameter to experiment in the horizontal pipeline, on which is arranged 5 pressure sensors and 10 flame sensors.
Table 1 Layout of the pressure sensors Serial number of sensor 1 2 3 4 5 The distance from the ignition source/cm 44 168 298 470 766 Table 2 Layout of the flame sensors Serial number of sensor 1 2 3 4 5 6 7 8 9 10 The distance from the ignition source /cm 44 64 168 188 298 318 470 490 766 786 2 Experiment result and data analysis of nano-aluminum powder explosion 2.1 Analysis of explosive pressure.

The influence of methods for converting torsion data (torque, number of turns and speed rotation) into equivalent variables (true stress, true strain and true strain rate) on the Garofalo equation parameters is studied.
Usually, the von Mises and Tresca equations are considered [10]: τσ 3=vM τσ 2=Tr (5, 6) On the other hand, the true strain and strain rate are obtained from the number of turns and the speed rotation.
Results and discussion Fig. 1 shows a set of torque-number of turns curves at 10 s-1 and different temperatures.
Torque-number of turns curves at 10 s-1 and various temperatures.
The decrease with strain observed in our work is related to the effect of dynamic recrystallization and probably to grain size reduction with strain.