Search results

Pulse electric field can refine crystal grain and increase the number of equiaxed crystal to different degree by these two techniques.

The supersaturated α-Mg with high-concentration Al regions occurred along the grain boundaries of the substrate, and β-Mg17Al12 intermetallics grew as lamellar and bulk precipitation from the supersaturated α-Mg regions due to coring effect during the casting process.
A large number of particles with 20-100 nm in size were observed in the solidification microstructure, and these nano-particles were found to be β-Mg17Al12 intermetallics based on SAD study (Fig. 2 (d)).

Thus, the initial reduction of Rsh is not related with interdiffusion processes, and may be explained by a decrease of the grain boundary density after recrystallization of Au layer.
However, after RTA at 800 o C the formation of small number of pores is observed (Fig. 4c).

A large amount of fly ash that produced by power plant in our country every year produce take up a large number of cultivated land and pollute environment without effective utilization.
According to the laboratory test, the physical properties of loess are shown in table 1: Table 1 Physical properties of the loess sample Nature moisture content / % Nature density / g/cm3 Nature dry density / g/cm3 Nature pore ratio proportion Plastic index Grain composition /% Clay Silt sand 12.6 1.38 1.23 1.195 2.70 9.2 18.5 74.0 7.5 The fly ash of test is taken from Lanzhou Thermal Power co., ltd.

The tested limestone must contain at least 85% of grains which are smaller than 32 μm.
LO1408 "AdMaS UP - Advanced Materials, Structures and Technologies", supported by the Ministry of Education, Youth and Sports under "National Sustainability Programme I" and by project No. 15-08755S: "Study of the effects of samples preparation on the final properties of inorganic binders" and project number FAST-J-17-4604 “Monitoring the properties of the limestone during thermal loading by DKTA, DSC and XRD-HT methods” References [1] BLASIO, Cataldo De, Ermei MÄKILÄ a Tapio WESTERLUND. 

Table 1 The orthogonal experiment of chitosan Compile Number A Time /h B Temperature /°C C Acetyl sulfonate /mL Sulfur content / % Color Solubility Molecular weight (´104) 1 1 20 7 9.10 Gray Insoluble 3.92 2 3 25 5 11.33 Khaki Soluble 3.25 3 5 30 3 10.91 Black Dissolve 3.18 4 1 30 3 10.39 Yellow and gray Soluble 3.76 5 3 25 7 10.04 Khaki Soluble 3.42 6 5 20 5 11.47 Yellow and gray Soluble 3.55 7 1 30 5 11.87 Gray Soluble 3.84 8 3 20 3 11.56 Khaki Soluble 3.21 9 5 25 7 9.22 Black Dissolve 2.89 R1 10.500 10.70 9.498 R2 10.997 10.357 11.557 R3 10.533 10.93 10.995 R4 1.492 1.577 3.054 Table 2 The impact of temperature on product sulfur content Temperature /°C 20 25 30 35 Sulfur content /% 10.29 11.56 11.33 9.60 Influence of reaction temperature.
Fig.4 was the SEM image of sulfonated chitosan samples, as can be seen from the graph [14], the nanoparticles with uniform size and better dispersion were approximately spherical, and the particle size was between 70 nm and 100 nm, but there was a slight reunion phenomenon, which was because the preparation of sulfated chitosan as particles was too small, the distance between the particles was very short between the particles, the van der Waals force was much greater than the particle's own gravity, causing the agglomerated particles which produced a certain attraction between grains [15].

Fatigue Crack Growth The following equation will be used in the analysis of fatigue crack growth: (2) Where a is the crack length, N is the number of cycles, A is a material constant of dimensions (MPa)-2, and is the effective range of ∆K at the threshold level which is taken to correspond to a growth rate of 10-11 m/cycle.
This change may occur when the plastic zone size in Ti-6Al-4V exceeds the alpha grain size and two slip systems can then act at the crack tip to propagate the crack.

The first reason is that the tinier granularity of grinding wheel on unit area, the more grains participate in grinding, the more nicks per unit area, the contour of nick is better, so the roughness value is smaller.
Table 2 Orthogonal bit-level form factors and results of orthogonal experiment The experimental plan Results Factor test number Grinding wheel granularity Grinding wheel linear velocity [m/s] Grinding camber ratio Transverse feeding [mm] Surface roughness [Ra/μm] 1 220# 10 0.60 0.030 0.60 2 220# 15 0.69 0.018 0.56 3 220# 18 0.78 0.010 0.48 4 W50 10 0.60 0.018 0.44 5 W50 18 0.69 0.010 0.32 6 W50 15 0.78 0.030 0.38 7 W40 18 0.78 0.018 0.21 8 W40 15 0.60 0.010 0.37 9 W40 10 0.69 0.030 0.41 1 A sum level 1.64 1.45 1.41 1.41 total sum 2 A sum level 1.14 1.31 1.29 1.21 3.77 3 A sum level 0.99 1.01 1.07 1. 23 range /R 0.65 0.44 0.34 0.20 Fig. 5 The measuring of hole surface roughness in optimum grinding parameters Conclusion The experiment analyzes the relationship between a variety of grinding parameters and the grinding roughness of the surface of zirconia ceramics spindle bore, with fine granularity the wheel bore surface roughness improved, but with the increase of lateral feed reduced

Accordingly, CCA is commonly applied to control the grain size and to modify the eutectic microconstituent of Al-Si alloys [7], and to control the chemical composition (carbon and silicon content) of cast irons [8].
For eutectic gray iron, an instantaneous nucleation model [20] was used, where the number of nucleation sites depends on the cooling rate of the melt when it reaches the eutectic temperature upon cooling.

After 30 redox cycles, the conversion rate of reduction is still similar, implying that the carrier’s reactivity was not affected by the number of cycles in use.
This can be explained by the redox cycle, in reduction process, there will be a lot of heat release out, then catalyst will generally exist hot spot effect, thus induced grain growth or the production of sintering phenomenon.