Advanced Materials Research Vols. 152-153

Abstract: On of the practical difficulties of high speed automotive hydraulic power steering is that the output exceeds the actual demands of the system, i.e., there is a substantial power loss. This paper discusses the configuration and the action principle of a new variable displacement of double-action vane pump, which consists of floating blocks. The pump belongs to an automotive hydraulic power steering system, and prosperous utilization is expected. In the meantime the mathematical and simulation model for hydraulic power steering of automobile were established and the Matlab Simulink simulation model was presented. Different parameters of pump are selected in simulating programming. The simulating results are analyzed and compared.

Abstract: A kind of U type 90°or V type 90°bending springback testing die was set up to discuss the bending springback . The springback of material can be masteried through setting up of bending springback adjusting test die without prior calculation . In order to adjust the bending angle , the T type slide seat and bending press plate were used and the adjusting of bending radii was implemented by replacing the adjusting axis of bending radii. At first, if the springback value of the sheet metal made sure for the die design , then the die was designed , the large of works for repaired and tested die were reduced and it will be the `most convenient for the die designer.

Abstract: Motivated by the widely discussed Ag doped ZnO and the lack of follow-up reports about the realization of p-n junctions, we calculated the electronic structures and optical properties of pure, Ag-doped and Ag-F codoped ZnO based on the density-functional theory. It was found that Ag doped ZnO shows p-type conduction character. But there are some unstable factors and self-compensations in this structure. We also calcualted the formation energy and ionization energy of the impurity for Ag-F codoped ZnO. It was found that incorporating the reactive donor F into Ag doped ZnO system, not only enhances the Ag acceptor solubility, but also gets a shallower Ag acceptor energy level in the band gap. In addition, we analyze the imaginary part of the dielectric function, reflectivity and absorption coefficient for pure ZnO and Ag-F codoped ZnO. Compared with the pure ZnO, the remarkable feature for Ag-F codoped ZnO is that there is a strong absorption in the visible-light region, which indicates that it could be taken as a potential candidate for a photocatalytic material.

Abstract: Effects of pH values on corrosion properties of 316L stainless steel were investigated to clarify the usability of 316L SS in circulating cooling water system. The polarization, EIS and Mott-Schottky measurements showed the superior corrosion resistance of 316L SS in the simulated cooling water solution with NaCl+Na2SO4. The Fe hydroxides and oxides products resulted in the passive film of 316L SS thicker during the cooling water convection, as the pH increased from 6.5 to 9.0.

Abstract: Composite of TiO2 and NaY zeolite was prepared by solid-state dispersion method and the simple mixture of TiO2 and NaY was also compared on methyl orange photocatalytic degradation. Methyl orange degradation rate increased constantly with the increase of TiO2 concentration from 50 mg/l to 200 mg/l and declined gradually afterwards. When the ratio of TiO2 and NaY zeolite was 1:10, the photocatalytic activity of the mixed catalyst was close to that of pure TiO2. The photocatalytic activity of TiO2-NaY composite in different ratio prepared by solid-state dispersion was lower than that of pure TiO2. The photocatalytic activity of the composite catalyst in the ratio of 1:20 was close to that of pure TiO2. Composite catalyst can deposit much quicker than pure TiO2 after treatment.

Abstract: By means of mechanical properties test and microstructure graph observation，the effect of core-shell Ni/TiO2 particles size, concentration on the properties and morphology of electrorheological fluid was emphatically studied, It is found that with concentration increasing the properties of electrorheological fluid can be improved, but there is a critical value, Urea content of Ni/TiO2 particles is 30%, in the same field with increasing concentration, particles chain of electrorheological fluid become strong，coarse and interweaved each other. The smaller of particle size, the higher of shear strength of electrorheological fluid.

Abstract: The stress concentration effect of different corrosion pits is different, the shapes of corrosion pits can be seen as semi-ellipsoidal, the short half axes、long half axes and depth of corrosion are 、 and , through finite element analyze, we can see that the stress concentration factors increase with the increase of , but the stress concentration factors decrease with the increase of .

Abstract: The lateral bend forming is a new flexible forming method which bend section steel into parts with all kinds of curvature. The main principle and advantages of lateral bend forming is introduced. Mathematical model of lateral bend forming is established based on finite element method. Contact problem is treated. The law of forming force versus process parameters is analyzed by numerical simulation technology. The results shown as follows: the forming force is increased with the increment of the pressing quantity; the higher yield limit of material is, the bigger forming force is; the forming force of angle steel is bigger than sheet metal without changing other parameters.

Abstract: In order to investigate the crack pattern of steel reinforced ultra high strength concrete (SRUHSC) column and steel reinforced concrete (SRC) beam joint subjected to reversal cycle load, six interior joint specimens were tested with various axial load ratio and volumetric stirrup ratio. A discussion on the ductility and crack pattern was presented. It was found that all joint specimens failed in shear fracture in the joint core regions and that axial load ratio had more influence on the crack resistance capacity. The experimental results indicated that test parameters of SRUHSC column and SRC beam joint with good crack resistance performance may be referred for engineering application.

Abstract: The concentration of TiO2 and the composites of TiO2 and 5A zeolite were studied in order to improve the photocatalytic activity of TiO2. Methyl orange aqueous solution was taken as imitated polluted water. The results indicated that the optimum dosage of TiO2 was 200 mg/l. A simple mixture was prepared by adding TiO2 and 5A zeolite together into methyl orange solution. The optimum TiO2:5A ratio was 1:11. Composite of zeolite 5A and TiO2 was also prepared using solid-state dispersion method. Photocatalytic activities of the composite after each preparation step were evaluated. Although the results showed that their photocatalytic activities decreased to some extent compared with pure TiO2, the composite could be easily separated from the treated solution.