Advanced Materials Research Vol. 661

Abstract: Stretching is a commonly used process to manufacture forgings with good quality. In this paper, the stretching process of cylinder forging with materials properties in materials engineering was investigated by finite element method. The metal flow law of cylinder stretching process was studied, based on the simulation and analysis of the effect of tool geometry like flat and V-shaped anvils on strain and stress distribution state in the forging. The reasonable tool geometry for stretching was V-shaped anvil.

Abstract: Using the method of electromagnetic coordinate transformation, through determination of the relation of permittivity and permeability distribution in different spaces, the forming condition of electromagnetic stealthy cloak made of metamaterial is discussed. On the specific distribution of permittivity and permeability, finite element method is used to analyze the electromagnetic characteristics of stealthy cloak which is radiated by plane electromagnetic wave. And the cloak shows excellent stealthy characteristic in theory at certain frequency of the wave. The result shows that the artificial metamterials, which are not found in nature, have the ability of controlling the electromagnetic field and changing the transmission path of wave. Besides stealthy cloak, new electromagnetic devices such as transparent device and concentrator, which are made of metamaterials designed by the coordinate transformation, are preliminarily discussed. They all have excellent stealthy characteristics.

Abstract: The interaction between tunnel surrounding rock and supporting structure has been deeply analyzed by using elastic-plastic theory, and the higher strength and durability of supporting structure made by selecting reasonable supporting structure and adopting high strength concrete as material has been proved.

Abstract: The candesartan cilexetil SMEDDS with PEG-PLA as long-circulating materials were successfully prepared and characterized by appearance, size and size distribution, morphology of emulsion and stability. The emulsion showed a narrow size distribution, well-proportioned in good agreement with polydispersity index of 0.005 and 3.6 nm diameter. The candesartan cilexetil SMEDDS were precipitated for 30 days at 25 °C or 37 °C. Meanwhile, Pharmacokinetics experiments illuminated that the candesartan cilexetil SMEDDS in rats had a larger drug curve concentration (AUC) compared to the tablets in the experiments.

Abstract: A huge number of buildings collapsed during the earthquake in Wenchuan. Recently, solid waste management of these post-earthquake wastes has becomes a major management concerns in Sichuan. As yet, no specific plan has been formulated for managing those components of the disaster. In addition to this, immediate efforts are needed to rebuild the collapsed houses within the city. Therefore, this paper aims to overview of some of the research published regarding the use of recycled waste or by-products in concrete blocks or bricks production. The mechanical properties such as compressive strength, tensile strength, water absorption and shrinkage are presented. Studies show that bricks and blocks can be made with recycled waste or by-products.

Abstract: Due to the applicable installation overhang large span, small mass, flexible characteristic, and small damp, the cable-stayed steel structure awning (CSSSA) could easily result in vibration with the wind load. The main factor is the turbulence wind and wind-rain induced vibration. Combining the structural dynamic theory, and considering the characteristic of the CSSSA, a motion differential equation is set up considering the wind-rain induced vibration, analysis cable-stayed stability under wind-rain induced vibration effect, and compare with the existing engineering result. Hope to provide some reference for similar designs.

Abstract: This paper presents the full-scale experimental tests on steel reinforced and non-reinforced interlocking brick beam utilizing interlocking brick system. Two specimens were tested with and without steel reinforcement embedded in the beam formed using interlocking brick. The purpose of this study is to investigate the performance of beam utilizing interlocking brick subjected to bending. The flexural behavior of the beam will be studied and discussed in this paper. It is concluded that the use of steel reinforcement in the beam has significantly influenced the flexural capacity. The results obtained from this study can be applied in the design of structure utilizing interlocking brick. Future recommendations are proposed in this paper for further improvements.

Abstract: Composites made from phenolic resin are filled with conductive filler mixtures containing copper powders, natural graphite powders and carbon fibers. They are fabricated by compression molding technique. The density, electrical conductivity and hardness of composite are analyzed to determine the influence of copper particle size on the physical, electrical and mechanical properties of composite. It is found that there is a marked dependence of the electrical conductivity and hardness on copper particle size. The hardness decreases with the decreasing of copper particle size. However the electrical conductivity increases with the decreasing of copper particle size. The decreasing of copper particle size from 75 µm to 48 µm promotes a considerable increase in electrical conductivity by about 427%. The increased continuous conductive metal networks could be the main reason for the increasing of electrical conductivity as copper particle size decreases. The results also show that composites containing copper particles of different sizes have the nearly same density.

Abstract: The effects of service environment will cause corrosion damage and fatigue cracks to initiate and grow, compromising structural integrity of the aircraft aluminum alloy structure. To develop an effective inspection and maintenance-scheduling program that takes advantage of life extension technologies, the sustainment engineering and residual life prediction method of aging aircraft aluminum alloy structure at service environment was proposed in this article. The whole algorithm of the sustainment engineering was described and the included situations of repairs, corrosion damage and widespread fatigue damage on aircraft structures were presented. At last, combining the results of FEM calculation with the AFGROW software of crack growth analyses, the residual life of corroded aluminum alloy structure was estimated.

Abstract: To perform the temperature compensation, a bimetallic thin film with different thermal expansion coefficients is deposited on the surface of the crystal plate. The thermal stress generated in the crystal and the thin film will cancel each other when temperature changes, thus improve the frequency stability of the crystal oscillator. In this paper, a finite element simulation was carried out for the crystal plate with bimetal, and then an experiment was performed to verify the FEM simulation results. The result shows that this approach achieves good temperature - frequency characteristics and reduces the frequency shift of crystal oscillator.