Advanced Materials Research Vols. 443-444

Abstract: In this paper, the approach for the contrarotating propeller parametrization modelling is provided based on the APDL language. Contrarotating propeller's parametrization modelling have several advantageous for the designers. The designers only need input some parameters, then the contrarotating propellers model could be produced automatically. Finally, this models are input into ANSYS to carry on automatically the strength analysis, and input into FLUENT to carry on the fluid analysis. It has saved the analysis efficience and has the very useful values.

Abstract: Metal aluminum was produced in a vacuum furnace using coal as reductant and aluminum chloride as chlorination agent and examined by means of XRD and SEM. The produced metal aluminum was impure. Reaction mechanism analysis showed that the carbothermic reduction of alumina with coal occurred following the chlorination, then metal aluminum was accquired and condensed on the collecting plate. A probable mechanism concerning carbothermic reduction and chlorination was discussed.

Abstract: Prepare poly butylene terephthalate (PBT)/multi-walled carbon nanotubes (MWNTs) composites through the method of melt blending. Then use low-cost single screw extruder to conduct experimental research and analysis on the extrusion test sample of PBT/MWNTs composites of different proportions under the conditions of changing the extrusion temperature, rate, cooling mode and so on. As a result, the process parameters of the better extrusion temperature, critical extrusion rate, and high-gloss molding etc. to reinforce the electrical properties of composites under low-cost experiment condition have been obtained. The experiment results also indicate that with the increasing of the MWNTs content, the surface resistivity of the composites shows a declining trend.

Abstract: Nowadays online quality estimation for the resistance spot welding (RSW) has benefited a lot from monitoring the electrode displacement caused by nugget thermal expansion. Based on these emerging monitoring techniques a new approach is proposed to classify the weld quality and assure the quality for mass-produced weld group, which enables the continuous quality improvement concept during the welding process. A causal models are built with the offline trained Bayesian Belief Networks (BBN). It is a weld quality assessment net reveals the dependency of the weld quality on the features displayed by the displacement curve, which can be used for overdesigning the safety welds or as the probabilistic forecasting model for online weld quality assessment. The experimental results show that the proposed approach is valid and feasible to predict the weld quality and assure the overall quality for weld group in real applications.

Abstract: Setting of tolerances to meet a required specification of quality characteristic and keep low manufacturing cost is one of common problems in the process quality control. But generally traditional tolerance design only focus on cost of manufacturing, few consider product Life Cycle Cost. In these situations, to obtain a satisfactory six sigma quality level as well as keep lower life cycle total cost should be considered. This paper expands tolerance optimization based on the manufacturing cost to the product life cycle cost, which can improve product quality to the six sigma level and keep lower LCC simultaneously.

Abstract: In order to solve the domestic intelligent electric actuator being low accuracy, poor and simple network communication function, this paper presents the development of small and medium power intelligent electric actuators based on TMS320F2812 DSP chip. This intelligent electric actuator has a few functions including network communication, high precise positioning, configuration, control and display self-checking. This type of actuator has compact structure and high intelligence. The advanced frequency conversion control method of vector magnetic beam is adopted in the process module of the actuator. Overall performance of the electric actuator is close to the international level.

Abstract: It is difficult to identify whether the ECS of a engine can overcome the HEMP environment, and if there are influences existing, how it will be affected and what extent it can. On the basis of discussing the occurring mechanics and characteristics of HEMP, a route to study the effects of the engine ECS under HEMP environment has been researched. Through the simulation of the HEMP, a laboratory test has been designed and carried out, and the influence of the engine ECS under HEMP has been analyzed. The research indicated that the engine ECS is susceptibility to the HEMP, the main damage mode is soft and transiency damage, it can make the control signal confusion and can even result in the suspension of work, but it can not make permanent hard damage to the ECS, and there are no evidence to show that the HEMP can result in an accumulation damage to the tested engine ECS.

Abstract: To improve the Electrochemical Machining accuracy and little stray corrosion of shaping hole, one scheme is adopted to carry on the technical experiment, which inserted the permanent-magnet into the core of cathode in the square hole separately. Compared with the experiment of Electrochemical Machining without magnetic field, the magnet around the core of cathode inlaid with the magnet is in favor of improving machining accuracy under the same processing parameter, and helpful to reduce the stray corrosion.

Abstract: To increase the efficiency of float valve tray in plate column, a combined directed valve tray was developed. Comparative analysis of tray pressure drops, entrainments, weeping rates and mass transfers was conducted between the widely used V1-type float valve trays and the combined directed valve tray. The applications of the combined directed valve tray in atmospheric pressure device, catalytic cracking unit and gas fractionation device were also listed, which indicated that it was a significant improvement of float valve tray.

Abstract: The blockage damage to the movable target on the ground with the mode of deterring is an important aspect of research about the fragment warhead. The analytic method of damage power about the blockage warhead cluster with the three blockage districts, including districts of dense damage in close distance, sparse damage in middle distance and deterrence damage in wide distance, was raised to do the research on the designing method of blockage damage warhead and the evaluation of blockage damage effect. The lying and standing static effectiveness test of the blockage warhead were designed based on the special blockage damage character. The designing method of the blockage damage warhead and the analytic method of blockage power characteristic were proved to be scientific, and the researching is significant in project application.