Advanced Materials Research Vols. 476-478

Abstract: The uniaxial and multiaxial non-proportional cyclic experiments of 16Mn steel under stress-control were carried out using MTS809 Series machine and Teststar control system .The influence of stress amplitude, mean stress and their loading history on uniaxial and multiaxial ratcheting is studied.

Abstract: On teeterboard flap of main rotor rotating around free space point of a 30Kg class unmanned autonomous helicopter (UAH), aerodynamics kinematics model is set up in terms of D' Alembert principle. On conditions of the helicopter physical parameter value, simulation validates the model in reason, and points out：①Teeterboard Flap on main rotor is self-stable system; ②unmanned autonomous helicopter structure plays a leading role on transient process of main rotor teeterboard flap, and relative air current acting on the blade plays a leading role on its steady process.

Abstract: The effects of different blending ratio on the properties of UHMWPE/ PP blends were studied in this paper. The result shows that when PP mass fraction is 50%, the heat deflection temperature of the blend is 90°C，which is 1.8 times higher than UHMWPE. While the wearability of UHMWPE/PP is decreased due to the addition of PP, it can be improved compensably by wear -resisting additives. And the notched impact strength of the blends is improved with the increasing content of UHMWPE.

Abstract: As the digital electronic engraving machine needs high speed and credible communication between a host computer and a slave computer, a data communication card for a high speed digital electronic engraving machine is designed and realized using PDIUSBD12 IC and S3C44B0X IC. PDIUSBD12 IC is USB interface device with parallel bus. In the paper, hardware circuit is described, USB driver program is depicted in detail based on the µC/OS-Ⅱ operation system, and the ways and means of debugging the data communication card are given. It has been experimentally validated that the data communication card is applied successfully and works steadily in high speed digital electronic engraving machines.

Abstract: 3D-ordered dumbbell-like ZnO microcrystals were prepared under hydrothermal conditions without using any additive, template or surfactant. FE-SEM images show that 3D-ordered dumbbell-like ZnO microcrystals are made of two elements-(Ⅰ) dumbbell-like microrods and (Ⅱ) nanorods that grow on the two ends of microrods. The thermal radiation properties of 3D-ordered dumbbell-like ZnO microcrystals were discussed in detail.

Abstract: A highly efficient γ-Bi2MoO6 photocatalyst was synthesized by a solvethermal method with the assistance of urea. The structure, morphology and photophysical properties of the Bi2MoO6 were characterized by X-ray diffraction, scanning electron microscope, UV–vis diffuse reflectance spectroscopy and nitrogen adsorption-desorption techniques. The photocatalytic efficiencies were evaluated by the degradation of rhodamine B (RhB) under visible-light irradiation, and the γ-Bi2MoO6 structures displayed significantly higher visible-light-driven photocatalytic activity in comparison to TiO2 nanoparticles.

Abstract: A new kind of machinable glass-ceramic was prepared by the sintering methods which has the high KIC, flexural intensity and other good mechanical properties so that it could be machined using the normal machinable methods such as turning, milling and drilling. The hardness and flexural intensity which was the main mechanical property factor influenced the machined ability was researched in detail with the help of TG-DSC, SEM, metalloscope, Hv hardness and flexural intensity measurements. Based on the orthogonal design methods (L2554) and numerical solution, the effects of the heat treatment about devitrification on the mechanical properties were analyzed and concluded that the mechanical properties was mainly influenced by the crystal temperature and heat holding time.

Abstract: It has been examined to disperse the Au nano-particles directly into liquid by replacing the solid substrate with low-vapor oil in a plasma sputtering apparatus. The dispersing particles in oil are much smaller than the conventional methods. Under low density of particles on oil, the intense absorbance peak is detected around 325nm and the shape and peak of absorption spectra don’t almost change following time, and the size of Au particles is steady. With higher density, the absorbance peak is stronger and shifts to visible light about 20nm. With prolonging measuring time, absorption peaks fall and a new absorption locating on around 550nm gradually appears, large numbers of particles gradually convert and produce the new particles sizes around 3-5nm. under high density, the other intense absorbance peak exists around 540nm besides the peak of 350 nm. High particles density produces the particles sizes around 5-7nm, and the contents and sizes of particles are basic invariablenes against measured period.

Abstract: In this paper，Al₂O₃ ceramic foam filters prepared by polyurethane sponge impregnation.The effect of multiple binders on properties of ceramic foam was studied . The results show that using 90g dihydrogen phosphate and 30g under the CMC 1350°C sintered alumina matrix ceramic foam filters are the best performance. The compressive strength of the Al₂O₃-based foam ceramics prepared with optimal multiple-binder and sintered at 1350°C could reach up to 1.697MPa. At the same time,it is obtained through test that the thermal shock times of sintered samples reached 5 by staying at 1100°C for 10 min.

Abstract: Porous alumina ceramic was prepared using sodium dodecyl benzene sulfonate (SDBS) as foaming agent by the combination method of gel casting and foaming. The effect of solid content on the line shrinkage rate, the porosity, the fracture strength and the microscopic structure of porous aluminum ceramic were studied. The result showed that when solid content increased, the line shrinkage rate of porous alumina ceramic decreased form 20% to 1.2%, the total porosity first increased and then decreased from 43% to 57%, the fracture strength first decreased and then increased from 23MPa to 41MPa. SEM indicated that alumina ceramic had more open pores when solid content was too low, the number of closed pore increased along with solid content rising, when solid content was too high, pore size distribution uniformity decreased.