Applied Mechanics and Materials Vols. 121-126

Abstract: In order to solve the question of safe distance between cross-cut and lower lane bolt tunnel and support, aim at geological and mining conditions of north mining area in sanjiaohe coal mine, and analysis mechanism of surrounding rock deformation, analysis the upper roadway surrounding rock stress, displacement and distruction of plastic by FLAC3D determine the minimum distance between the two tunnel and design support scheme on the basis of on-site roadway conditions. Result of this study can provide a reference not only in this mine but also for another similar situtions roadway.

Abstract: Modularity design is a comon method in product design.This essay is about the analyzing of the application of modularity in military product design,study on the developing trend and value of modularity in military products by analyzing the advantages of moularity and it’s major features in military products.

Abstract: As one of the key components of the nuclear power equipments, the nuclear channel head has a complicated shape and is difficult to be machined. In this paper, the optimal combination of cutting parameters of large-scale nuclear channel head is researched. Considering the machining requirements and machining conditions, the cutting parameters optimized mathematical model is established to achieve the goal of maximum production efficiency. Meanwhile, the target functions and the corresponding constraint functions are analyzed. Finally, by using genetic algorithm of simulating biological evolution, the mathematic models of cutting parameters of CNC machining are compared and optimized. Then the optimized results are compared with the cutting parameters obtained through the trial-producing experience and manual of a small-size channel head. We conclude that the optimized cutting parameters can greatly increase the CNC machining efficiency of Nuclear Channel Head.

Abstract: Based on the analysis of Dual clutch transmission (DCT) working principle, the shift kinetics model is established, and the power switching rule between two clutches during upshift and downshift is established by analyzing the torque transmission relationship of vehicle driveline system during shifting, then shift process is tested on actual vehicle with Matlab/Simulink software. Comparing the two different kinds of downshift processes, and illuminating the effect on engine control by various downshift control rules, the downshift process is optimized.

Abstract: With the development and application of automation and information technology, missile equipment become increasingly sophisticated and complex, combined with cost, quantity,safety and other factors, maintenance and support the missile equipment face enormous challenges.This paper introduce firstly the virtual maintenance technology, and then propose the main functions and tasks of missile equipment virtual maintenance system based on virtual maintenance technology and take active interest in the development and application of domestic and foreign research results.

Abstract: In order to change the traditional status that rolling mill liner can not be manufactured with a single material, laser transformation hardening was carried out by HL-1500 cross-flow CO2 laser processing machine on 45 steel surface. developed a non-composite liner instead of the original. The microstructure and properties were researched by means of scanning electron microscopy, X-ray diffractometer, microhardness tester and abrasive wear testing machine. The result indicate that, the microstructure of laser transformation hardening layer fine and homogeneous, mainly composed of Fe, Fe3C, Fe-Cr and Cr3C2, the hardness and the relative wear resistance are about 3 times and 2.7 times as that of the substrate respectively; which can reached the technical requirements liner needed.

Abstract: The cutting performance and wear mechanisms of whisker-toughening ceramic cutting tools synthesized by carbothermal reduction process have been studied when cutting the hardened alloy steel 40Cr. It is indicated that the wear resistance of ceramic tools is affected by the molar ratio of C and N in tool materials. At low cutting speed, the main tool wear mechanisms are abrasive wear and oxidation wear. At middle and high cutting speed, the tool wear mechanisms are controlled by abrasive wear, adhesive wear, diffusion wear and oxidation wear simultaneously. Adding whiskers to the matrix material is one of the effective means to improve the wear resistance of ceramic cutting tools.

Abstract: Tooth contact analysis (TCA) is an effective tool for meshing analysis of the double circular arc profile spiral bevel gear (DCAPSBG), and it is the basis of loading tooth contact analysis and finite element analysis. The TCA application is developed by Visual Basic and MATLAB mixed programming method, this paper compared the results of the TCA application analysis with the results of contact area check experiment on one pair of gears with given parameters. The TCA application had been verified by real experiment, this provided an effective approach for the design of DCAPSBG.

Abstract: How to quickly and accurately detect the error of NC machine has become a hot issue for domestic and foreign scholars. Based on GPS principle, a laser tracker is adopted the multi-station and time-sharing measurement to rapidly and accurately detect the geometric accuracy of NC machine. The machine is controlled to move in the preset path, and a laser tracker is used to measure the same motion trajectory of the machine successively at different base stations. The position of base station and the space coordinates of measuring points can be determined based on large amount of measured data. The algorithms of multi-station and time-sharing measurement are given, and the influencing factors of measurement results are discussed in the paper. Meanwhile, a detection system of machine error is developed based on the platform of Matlab, which can quickly process the measured data and shows each error of machine intuitively.

Abstract: To meet the requirement of mass customization of garbage truck, knowledge engineering plays an important part in modern garbage truck design. As the basis of knowledge engineering application, the principles of common knowledge representation methods were analyzed in detail, and the application places of different knowledge representation methods were presented in the paper. Finally, examples of production knowledge representation, sate space representation, object-oriented knowledge representation, and semantic network-based knowledge representation were introduced independently to show the feasibility of applying these methods on the design of loading device of garbage truck.