Advanced Materials Research Vols. 314-316

Abstract: Conventional methods of design to be completed ordinary hydraulic transmission gear gearbox design, but for such a non-planet-rule entity, and the deformation of the planet-gear contact stress will have a great impact on the planet gear, it will be very difficult According to conventional design. In this paper, ANSYS software to the situation finite element analysis, the planetary gear to simulate modeling study.

Abstract: Because the side-blown protection effect in the laser welding is insufficient, and its convenience and flexibility are restricted. Laser welding coaxial protection nozzle is designed and trial-manufactured. According to the characteristics of laser welding protection, through rational design of nozzle structure, two protection gases are respective controlled .Using the coaxial nozzle for stainless steel laser stitch welding test, its influence on protect effect and the welding process are analyzed. The result indicates that the structure of nozzle’s gas path, gas outlet designed reasonable, venting uniform, protection effect is good. And it can reduce welding splash to focus lens, has certain protection effect.

Abstract: This paper describes a new active optical alignment method that is developed for the alignment of optical fibers to planar waveguide in order to improve the precision and efficiency of that. A new coupling mode, which is a polynomial function, is rebuilt by simplifying effect factors of the light field coupling process, such as angular offsets and line offsets. The optimum curve which is calculated to fit those sampling points by taking advantage of the least square method assists to locate the maximum coupling point of the alignment. Simulation results show that the alignment of two single mode fields is improved into 0.1μm precision with only 6 sampling points by the new method instead of 0.4μm offset with average 21.4 sample points by hill-climbing method. Using this alignment method, a fiber-to-waveguide, high-efficient coupling that provides higher accurate alignment with less sampling points is achieved.

Abstract: This article adopts genetic algorithm to solve the problem of guillotine rectangular stock cutting, and designs a new crossover operator and mutation operator towards the specifical problem, finally gives an example to prove this new genetic algorithm is effective to solve the rectangular cutting problem

Abstract: According to the calculation model of the keyhole porfile[1], the 3D point cloud data is calculated. Then, the paper establishes a physical model of the keyhole in the laser welding by using the 3D reverse technology. The adaptive mesh generation of the model is processed by the independent development software. Finally this paper establishes a mathematical model of the temperature field in the laser welding, which considers the factor of the welding velocity. A more accurate temperature field is obtained by using the laser welding solver which is a secondary development of OpenFOAM, adding the Guass surface source and the keyhole volume source, and setting the boundary condition of convection and radiation. The result provides more accurate bases for the welding stress field.

Abstract: A vector calculation method is proposed to compute the tool envelope surface in five-axis machining. By introducing the typical five-axis machine tool motion, the velocity of cutter is obtained with rigid body motion theory. Based on envelope theory and some geometric characteristic of the cutter, the envelope condition is be simplified to find the grazing point with vector calculation method. The results can be applied to NC machining simulation, toolpath verification and optimization.

Abstract: Ejection seat is the most important life-saving tool in warcraft. We analyze of the reason why the ejection mechanism works in advance in ejection process, when the aircraft canopy is not throw away. And carry on the deformation analysis of the lock arm in the interlock device to define the strength of the lowest part of the lock arm. Finally, we obtain the stress distribution graph of lock arm, which provides a theoretical reference for the interlock device on the optimal design.

Abstract: The three-dimensional numerical simulation model of two polymer melts flowing through the traffic circle section path was founded. The coextrusion process of composite pipe was simulated used the finite element method. The stream line method was used to simulate the extrudate swell. Such simulated results as the location and shape of coextrusion interface, the shear stress profile were analyzed. It is found that the maximum shear rate occur near the convergence section of the outer polymer. The interface excursion is less than 1mm in the die path. As the melt flow out of the die, the interface excursion increase distinctly, the value is up to 6mm. The extrudate swell rate is 21% along the radial direction.

Abstract: The method was proposed by use of the finite element analysis software ABAQUS and the BP neural network technology to build a synthesis error prediction model of a machining-center. Firstly the finite element model of a vertical machining center CINCINNATI ARROW750 was created by use of ABAQUS ,and the cutting force induced error was analyzed which resulted from the deformation of the machining-center’s components that was caused by the cutting force ;Secondly the geometric error of the machining-center was measured by use of the laser interometer,and the sample of synthesis error was obtained. Finally the synthesis error prediction model was obtained by use BP neural network,and through the comparison of predicted value and actual value of 25 groups of samples, the feasibility of error prediction model was verified.

Abstract: The history and application of the FEA are briefly presented in this paper. Several key technologies such as the building of material model, the establishment of the chip - tool friction model as well as meshing are described. Taking the high-speed cutting of titanium alloy (Ti - 10V - 2Fe - 3Al) as an example , reasonable cutting tools parameters are determined by simulating the influences of cutting temperature, cutting force on the tools parameters using FEA.