Advanced Materials Research Vol. 487

Abstract: It’s well known that bulk Fe-based amorphous alloy is difficult to fabricate, but we develop low price Fe-based amorphous alloys applied in practice after systemic analyzing and considering the cost demand of the application. Finally, there are 7 Fe-based amorphous alloys fabricated by advanced copper mold casting after careful attempt.

Abstract: There are 7 Fe-based amorphous alloys fabricated by advanced copper mold casting after careful attempt. The electrochemical property of amorphous alloys was studied for investigating the physics characteristic and properties applied in practice further. The result is as follows: Amorphous alloys exhibit good corrosion resistance in NaCl solution and HCl solution, and the addition of Cr and Mo can improve the passivating ability.

Abstract: The porous Ti plates with nanograde pore size were successfully prepared by dip-coating technique, using stainless steel plates as support and 400mesh Ti powders as raw material. The stainless steel plates were firstly dipped into Ti slurry and then pulled out with desired withdrawal velocity. After sintered in a vacuum furnace, stainless steel supports were removed by aqua regia. The obtained products were characterized by X-ray diffraction, sanning electron microscope and N2 adsorption–desorption isotherms. The results had shown that the thickness and pore characters of porous Ti plates could be controlled by adjusting the withdrawal velocity. When the withdrawal velocity was controlled between 0.2mm/s and 1mm/s, the porous Ti plates had smooth surface without cracks and the most pores were interconnected. The maximum pore diameters could be less than 300nm and the porosities of porous Ti plates are more than 4.9%. The kind of preparation method has advantages of simple technology, easy operation and high purity. These indicated that the porous sintering Ti plates were promising to be used as ultrafilter membranes.

Abstract: The estimation of grain size is the important basis of metallographical analysis. The definitions of grain size, area, average area, chord, major axis, minor axis, diameter and average diameter are given in this article. A filling-and-elimination counting method is also introduced to count the number of grains in the digital steel microscopic image. The equations for calculating average area and diameter of grains are presented too. Finally, an algorithm for calculating grain’s average diameter is given. The experimental results show that the proposed approaches are efficient and practical.

Abstract: 1-3 orthotropic cement based piezoelectric composites were fabricated by cut-filling and arrange-filling technique, using PZT-51 ceramic as functional material and cement as passive matrix. 1-3 orthotropic cement based piezoelectric composites were prepared into Acoustic Emission (AE) sensors, the attenuation of AE signal on the concrete and the response of different sensors on the concrete with increasing distance were researched. The results showed that the signal strength received by sensing element increases with the increasing PZT volume fraction; signal peaks and amplitude decrease gradually when the testing distance increases; signal strength received on the ceramic title is stronger than on the concrete; the attenuation of signal wave shape received on the concrete is much slower when compared with ceramic title.

Abstract: The paper discusses the contents of ecological safety strategies in the ecological safety design and the eco-city planning, the strategy of earthquake resistant materials and structural strategy, the appropriate technology, reliable technology and conceptual design of earthquake engineering, the major controllable factor in the ecological safety strategies, and then examines effective planning and design, the relationship between urban life and it’s planning, architectural function and the personal safety problems, selection of appropriate sites and environmentally sustainable site development, etc. In the case of seismic emergency, the best way is to alter public spaces into disaster prevention area, provide enough area for creating disasters prevention strongholds. In addition to these, the article studies the relationship among the urban ecosystem and the building ecosystem, the planning and design integrated ecology, the method of interdisciplinary working. This article also argues the problems of ecological safety strategies in the urban planning and the architecture design, and the main contents of ecological safety strategies under the concept of low-carbon strategy. From a whole urban ecosystem, to a building ecosystem, some strategies of eco-city planning and ecological safety design are studied. It includes the strategies of urban environment and sustainable development under the principle in low-carbon strategy, which is in conflict with rapid economies and ecological conservation.

Abstract: The use of advanced composite materials reinforced with fibers is expanded in these years. The main reason for the increased use of these materials is their high strength and hardness coefficient, their density and low prices. So, the fiber-reinforced composite materials can be used in the design of structures that require high strength to weight ratio and hardness coefficient. In order to replace these materials and new applications, many research programs to study the mechanical behavior of these materials has shifted. In this paper Finite element model presented in which the fibers and matrix are modeled separately and to show a full description of the properties of the constituent components, the interface between matrix and fiber discontinuity is presented in the model With using modeling and analysis after great determination of mechanical properties of unidirectional fibrous composite single and compared with experimental results, the elastic modulus changes depending on the angle of the fibers is received . The results of this method are compared with available mathematical models.

Abstract: In the present work, the rheological model (CF model) developed by Chen and Fan[1] for semisolid metal slurries (SSMS) is applied to investigate the thixotropy of the AlSi6Mg2 alloy under cyclic shear deformation. The present investigation indicates that the semisolid AlSi6Mg2 alloy has the thixotropy by the technique of hysteresis loop. Specifically, the area of the hysteresis loop increases with decreasing the up-time, the initial shear rate and increasing resting time, solid volume fraction and maximum shear rate, respectively. These results agree qualitatively with the experimental data. Furthermore, the origin of the hysteresis loop is attributed to the difference between the agglomeration rate and the deagglomeration rate.

Abstract: The Lattice Boltzmann Method has emerged as an alternative and powerful tool for simulating complex fluids in complicated geometry. It can help us to predict the revolution of the pollution after the industry accident. In this paper, we focus on the need for using Lattice Boltzmann Method to simulate the pollution propagates.

Abstract: Concerning the nonuniformity problem when sampling in current single grain moisture on-line inspection devices, this paper designed a new grain sampling device by analysing the physical property parameters of grains. The design of the sampling device is optimized by combining computer mode and physical experiments. In condition of ensuring single grain sampling, fixed the structure parameters of sampling rollers for South grains and North-east grains. The structure parameters of South grain sampling roller groove is length 18mm, width 2.5mm, depth 3mm. The structure parameters of North-east grain sampling roller groove is length 15mm, width 4mm, depth 4mm.