Applied Mechanics and Materials Vol. 203

Abstract: Energy efficiency is considered as a challenge in Wireless Sense Networks because of the limited energy. In this paper a novel grid-clustering sensing algorithm, the SCA (the sensing clustering algorithm) is proposed in order to minimize energy expenditure and maximize network lifetime. Different to all conventional methods, the proposed algorithm clusters nodes depending on the sensing ability, and forms a comprehensive covered and fully connected network. Both of the theoretical analyses and the simulation indicate that the SCA reduces the energy consumption effectively.

Abstract: The paper described a new magnetometer with cesium vapor in the spin-exchange-relaxation-free (SERF) regime. The variation behavior of phase retardation of the /4 wave plate (in the probing beam direction of this magnetometer) with temperature was introduced, which directly affected the sensitivity of the magnetometer. A detail theoretical analysis was expressed to give the temperature properties of a quartz wave plate. The retardation reduced 0.84 when the temperature increased 1°C for the wave plate with thickness of 2.24 mm and wavelength of 852 nm. According to the various phase retardations of wave plate in different temperatures, the relative intensity of the detection signal in this magnetometer was proposed.

Abstract: Recently, atomic magnetometers have been reported as the most sensitive magnetometers by completely eliminating the spin exchange relaxation. In this paper, we described a design of highly sensitive cesium atomic magnetometer based on circular dichroism, which had the advantage of easily locking the probing laser to the necessary frequency compared with those based on circular birefringence. In order to polarize the cesium atoms uniformly, the pumping laser light was separated into two counter-propagating and counter-circular polarization beams through the atomic vapor cell. We employed a circular analyzer optical configuration to measure the ellipticity of the probing light, which indicated the amplitude of the magnetic field. The external magnetic field was tracked by a digital auto frequency tracking system.

Abstract: A special designed 2D accelerometer was successfully used in the design of the minitype 2D vector hydrophone. The theory, design and experiment test data of both the accelerometer and the vector hydrophone was presented in this paper. The accelerometer based on cantilever beam mode and used PZT tube to substitute the PZT plate which was traditional used, this substitution enhanced the mechanical strength of the accelerometer, which resulted to the high performance of the 2D vector hydrophone in its natural frequency and sensitivity. The outside electrode of the PZT tube was divided into four equivalent parts, and each opposite part was wiring connected into one accelerometer channel, thus the two orthotropic accelerometer channels was integrate into one 2D cantilever beam mode accelerometer. The minitype vector hydrophone was designed based on this compact 2D accelerometer, and it’s high performace makes it possible to be used in under water sonar transducer arrays.

Abstract: With the rapid development of modern world aerospace science and technology, hi-tech weaponry and high-speed transportation tools, industrial production and high-tech equipment manufacturers have increasingly urgent demand for high-performance metal materials. The cast aluminum is a new aluminum alloy series developed by foundry industry recently. Because it does not need the solid solution hardening process and has good mechanical properties, it's loved by the manufacturing sector. This paper targets at channel angular deformation direction to study the cast aluminum tissue material .

Abstract: Motor rotator is one of the most important cast aluminum members. The configuration is so complex that it spends so much calculation and time by experimental method using multi-program. This paper mainly researched several main parameters by using scientific experimental method, thus introduced a simple project with optimized parameters in order to achieve a goal that can reduce in workload and improve the quality of castings.

Abstract: The high-silicon aluminum alloy by spray deposition forming is well suited for the engine cylinder liner because of the need of high strength and abrasion resistance, but its forming process is much complex, and many process parameters are involved. In order to lower the investments of time, labor power and money due to the traditional processing methods that need to adjust the craft parameters frequently, the thermal extrusion process and the spinning process that are the most important forming processes in aluminum alloy cylinder liner forming are simulated by the finite element simulation technology. It is found that during the extrusion process, the equivalent stresses near the die are larger, and uneven, the stress gradient is very large, but the maximum stress does not exceed the allowable stress of the material through the numerical simulation; In the spinning process, the stress and deformation are larger at the beginning of the process, but they will have a slight decreasing with the spinning process going on. Throughout the spinning process, the equivalent stress and strain distribution of the spinning component maintained a relatively balanced state basically, which is consistent with the later experimental results. It proves the reliability of the the simulation.

Abstract: Single phases of TbxY1-x Al3(BO3)4（0≤x≤0.2）phosphors were synthesized by a sol-gel combustion method with citric acid as fuel and complexing agent. Our method involves only exothermic decomposition of an aqueous citrate–nitrate gel and the gel yielded nanocrystalline TbxY1-x Al3(BO3)4 phosphors at 1000°C, without any formation of intermediate phase. The optimal doping concentration of Tb3+ ions in the serials was found to be approximately 12mol%. The decomposition of the gel was investigated by TG–DTA. The product has been further characterized by X-ray powder diffractometry (XRD) and fluorescent divide spectroscopy (FDS).

Abstract: In recent years, the feature technology has been widely used in CAD/CAPP/CMA design. This essay comprehensively analyzes and studies on the feature definition, description and expression, according to the characteristics of the welded structure design. Welded structure products feature models applicable to the pressure vessels are developed and designed against the product structure features of, welding types of and connector design requirements for the typical welding structure pressure vessels and by combination of the feature technologies. The feature design of the welded structure is studied by the analyzing the welded structures of the pressure vessels. By study on the welded structure design technologies based on features, parametric design technologies can be applied in the development of the welded structure products to effectively shorten the product development circle, improve the product development quality and increase the levels of information technology applied by a firm.

Abstract: The paper analyzes the precipitation behavior of micro-alloy elements including Nb, V, Ti and its effect to ductility of the steel during thermal deformation process, study on relationship between Nb, C content and slab crack incidence rate, supply countermeasures to control crack incidence rate during continuous casting course from components adjustment and process discipline optimization.