Advanced Materials Research Vols. 418-420

Abstract: This paper describes a novel inductive accelerator and investigates some of the parameters affecting its performance. As a important component of the accelerator, the resonator is composed of a new-style tunable inductor and a fixed capacitor. When an acceleration is applied on the resonator in the vertical direction, we can acquire the acceleration value by measuring the changes of the resonant frequency passing through a differential frequency circuit. Design and simulation, we get out the frequency of the accelerator is proportional to the acceleration, inductance variation ranges from 0 to 0.2*10^-9H, and frequency variation is from 0 to 5.7*10⁹HZ when the capacitor spacing is 2um. We use SU-8 photoresist to fabricate thick metal layer.

Abstract: In order to study the effect of laser shock processing (LSP) on titanium alloy, a TC4 alloy sample was processed by Nd:YAG laser with the wavelength of 1.06μm and pulse width of 12ns, and its micro-hardness and residual stress were examined and analyzed. The experimental results show that an evident strengthening layer of sample forms in the laser shock processing area. Laser shock processing improves micro-hardness and residual compressive stress of the sample significantly such as surface micro-hardness increases by up to 28.4%, the tensile stress changed into compressive stress, the layer of compressive stress distributes more than 1mm in depth and the compressive stress in the surface reaches up to -304MPa with 5J pulse energy. The effect of laser shock evidently strengthens the TC4 alloy, which improves the fatigue life of the aviation material and the performance of resist stress and rust by a large margin.

Abstract: A computational fluid dynamics(CFD) based numerical model is developed to predict the temperature distribution during Friction Stir Welding(FSW) of dissimilar aluminum alloys. The effect of tool rotation speed and axial pressure on heat transfer during FSW has been studied. Numerical results indicate that the maximum temperature in FSW process can be increased with the increase of the axial pressure and tool rotation speed. The influence region of the tool shoulder in the direction of thickness can be increased with the increase in the axial pressure on the shoulder.

Abstract: To solve the problems of change design and massive work and low efficiency during Cast & Roll processes design, an expert database system for Cast & Roll process design of copper tubes has been developed. Knowledge reasoning, Artificial Neural Networks (ANN), Genetic Algorithm (GA), Numerical Simulation, Uniform Design, CAD Parameterization Design, database and Intranet have been integrated into the system for process design and parameter optimization, which can exert the advantage of each technology. The design method has been proved to be successful.

Abstract: The article introduces each component of feeding paper machine of printing press which are press feet mechanism, paper separation mechanism and paper transfer mechanism, the function and the principle of work. Each mechanism is undertook a variety of designs and we choose the best design of each structure according to its functions. Design adopted is as follows: Press feet mechanism adopts the cam-linkage mechanism; Paper separation mechanism adopts the cam-linkage slider mechanism; Paper transfer mechanism adopts the conjugate cam-linkage slider mechanism. The machine is simple, practical and reliable.

Abstract: When liquid within short pipe is placed suddenly into low-pressure environment from an atmospheric pressure, the effects of temperature and pressure on occurrence and developing of evaporation wave are studied, the variations of flow patterns are observed. The experimental results show that flow patterns of liquid within short pipe gradually change from bubble rising to blazing bubble flow until annular flow with a decrease in initial environmental pressure. Intensity and moving speed of the evaporation wave increased with a decrease of the diameter of pipe and pressure, and an increase of the fluid temperature. The evaporation wave fronts are in a state of explosive vaporization, instantaneous propagation velocity of evaporation wave fronts is violently fluctuating.

Abstract: This paper studies the aperture phase errors of reflector antenna based on the interval method. Through the interval matrix perturbation algorithm and the interval truncation algorithm, the effect of surface nodal displacement intervals on the aperture phase errors is obtained. The numerical example of an 8m diameter reflector antenna shows that the method is rational and feasible.

Abstract: In wireless network communication system, the complexity of communication system makes it difficult in experimental teaching and studying transmission interference. As collision probability is an important factor in transmission interference, the model to compute collision probability is very necessary. In this paper, an algorithm is proposed in computing collision probability based on handoff model. Then, a related hardware and software platform is established for analyzing transmission interference in high speed railway system. In simulation, it proves that collision probability can be decreased if the time of sending packet is changed.

Abstract: Abstract. Introduced the current situation drainage network of Zhenjiang and the problems of traditional information management, combined geographic information technology and decision support technology, using vb as a tool to develop Zhenjiang drainpipe network management information system, tell the structure and the target function, describe the completed part of the system, shows the results of JiangBin Hospital pilot project, the established system improves the shortcomings of traditional drainage network management, raises efficiency.

Abstract: A new process of hot precision forging the clutch gears was put forward. The most suitable shape of blank is designed which forms the clutch gears easy by precision forging. A practical die structure is presented for a hot precision forging the clutch gears in this treatise. A powerful die separator on the die forces the forge piece to break away from male die as soon as the hammering is over. The key technical problems that the hot forge piece sticks to the male die are solved. The improvement on technique and the economic benefit are very remarkable.