共查询到20条相似文献,搜索用时 15 毫秒
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Precision forging of the helical gear is a complex metal forming process under coupled effects with multi-factors. The various
process parameters such as deformation temperature, punch velocity and friction conditions affect the forming process differently,
thus the optimization design of process parameters is necessary to obtain a good product. In this paper, an optimization method
for the helical gear precision forging is proposed based on the finite element method (FEM) and Taguchi method with multi-objective
design. The maximum forging force and the die-fill quality are considered as the optimal objectives. The optimal parameters
combination is obtained through S/N analysis and the analysis of variance (ANOVA). It is shown that, for helical gears precision
forging, the most significant parameters affecting the maximum forging force and the die-fill quality are deformation temperature
and friction coefficient. The verified experimental result agrees with the predictive value well, which demonstrates the effectiveness
of the proposed optimization method. 相似文献
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A. Saravanan C. Balamurugan K. Sivakumar S. Ramabalan 《The International Journal of Advanced Manufacturing Technology》2014,72(9-12):1219-1225
A new forming technology of car steering knuckle was presented, aiming at eliminating the defects in the existing steering knuckle forming process. Based on orthogonal experimental design to numerical simulation by using FEM, for steering knuckle closed extrusion of multi-objective optimal design problems in systematic research, the influences of extrusion temperature and speed, mold temperature, and lubrication of forming technology were discussed with comprehensive scoring method and integrated balance method, then the process parameters used in the forming were applied in the productive practice. Results show that the orthogonal test method combined with finite element simulation can be flexible and efficient in handling of multi-objective optimization problems. As for the forming of other types of long rod fork forging, the new process and the design method have important guiding significance. 相似文献
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H. Ou 《The International Journal of Advanced Manufacturing Technology》2006,31(1-2):61-70
This paper presents an approach to predict dimensional errors in 3D complex shapes due to press geometry errors and elasticity. Using a press stiffness matrix formulation for the press deflections in forging operation, a quantitative relationship between forging die deviations and the press geometry errors and elastic deflections is developed, which is a function of the forging force, press stiffness and the spatial relationship between the forging dies and the press table. The stiffness matrix of a screw press is obtained using finite element analysis. To evaluate the effect of the press elasticity on dimensional errors of 3D components, a case study of forging for aerofoil shapes is carried out based on the results from physical modelling experiments. With the representative information of the tool shape and forging force data, numerical results of the forging die deviations as a source of dimensional errors for the aerofoil shape are obtained and evaluated. It is demonstrated that this approach is applicable to forging and other metal forming processes for complex shapes. 相似文献
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Bing Li T.J. Nye Don R. Metzger 《The International Journal of Advanced Manufacturing Technology》2006,28(1-2):23-30
Tube hydroforming is an attractive manufacturing technology which is now widely used in many industries, especially the automobile
industry. The purpose of this study is to develop a method to analyze the effects of the forming parameters on the quality
of part formability and determine the optimal combination of the forming parameters for the process. The effects of the forming
parameters on the tube hydroforming process are studied by finite element analysis and the Taguchi method. The Taguchi method
is applied to design an orthogonal experimental array, and the virtual experiments are analyzed by the use of the finite element
method (FEM). The predicted results are then analyzed by the use of the Taguchi method from which the effect of each parameter
on the hydroformed tube is given. In this work, a free bulging tube hydroforming process is employed to find the optimal forming
parameters combination for the highest bulge ratio and the lowest thinning ratio. A multi-objective optimization approach
is proposed by simultaneously maximizing the bulge ratio and minimizing the thinning ratio. The optimization problem is solved
by using a goal attainment method. An example is given to illustrate the practicality of this approach and ease of use by
the designers and process engineers. 相似文献
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单向压紧制孔工艺的自适应响应面优化方法 总被引:1,自引:0,他引:1
针对轻型自动化制孔系统的单向压紧制孔工艺,提出了一种基于自适应响应面法的单向压紧制孔工艺参数优化方法。该方法仅通过少量样本点的有限元分析,即可构建可靠的自适应响应面,避免了优化迭代过程中的有限元仿真分析,大大提高了计算效率和精度。以飞机机身框间对接结构为例,构建了自适应响应面模型并进行参数优化,给出了该典型结构的工艺参数推荐值。优化结果表明,压紧力大于和小于最佳值都会造成贴合面间隙过大,采用合理的压紧力是工艺实施的关键。最后通过试验结果验证了所提方法的有效性。 相似文献
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在直齿圆柱齿轮两步成形冷精锻工艺中 ,预锻模具齿形设计对改善材料填充性能 ,降低成形载荷具有重要意义。本文采用正交试验法与数值模拟技术相结合的方法 ,来解决预锻模具型腔优化设计问题。选取了描述预锻模具几何形状的 3个参数作为影响因素 ,以预锻终锻总载荷值为指标 ,通过有限元模拟分析来获得虚拟试验结果 ,最终确定预锻模具型腔几何形状参数的最佳值 ,为提高齿轮精锻成形质量提供有效依据。 相似文献
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TC4合金叶片精锻过程的二维数值模拟 总被引:3,自引:0,他引:3
采用刚塑性有限元法对钛合金精锻叶片的锻造过程进行了二维有限元数值模拟。在数值模拟过程中 ,考虑了摩擦边界的作用和畸变网格的局部重划分。根据数值模拟结果 ,研究了不同锻造工艺参数 (变形温度、变形速率、压下量等 )对叶片锻造过程中的变形力、应力和应变变化的影响规律。 相似文献
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M. Sanjari A. Karimi Taheri M. R. Movahedi 《The International Journal of Advanced Manufacturing Technology》2009,40(7-8):776-784
In this study, the artificial neural network (ANN) and the Taguchi method are employed to optimize the radial force and strain inhomogeneity in radial forging process. The finite element analysis of the process verified by the microhardness test (to confirm the predicted strain distribution) and the experimental forging load published by the previous researcher are used to predict the strain distribution in the final product and the radial force. At first, a combination of process parameters are selected by orthogonal array for numerical experimenting by Taguchi method and then simulated by FEM. Then the optimum conditions are predicted via the Taguchi method. After that, by using the FEM results, an ANN model was trained and the optimum conditions are predicted by means of ANN (using genetic algorithm as global optimization procedure) and compared with those achieved by the Taguchi method. The optimum conditions are verified by FEM, and good agreement is found between the two sets of results. 相似文献
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Circular-arc aerofoil flat plates are analysed for their vibrational characteristics using the finite element approach. The effect of variation in the lune angles of the aerofoil plates, on natural frequencies and mode shapes is investigated. Two types of plate bending finite elements are used in the investigation; one is the conventional nine degree of freedom triangular element and the other is a modified triangular element with one edge curved. The later element has been specially developed and used near the curved boundaries of the plate, whereas the former straight edged element is used in the interior. The results of the finite element analysis are verified through experimental investigations. 相似文献
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Yong Shao Bin Lu Hengan Ou Facai Ren Jun Chen 《The International Journal of Advanced Manufacturing Technology》2014,71(1-4):69-80
Preform design plays an important role in forging design especially for parts with complex shapes. In this paper, an attempt was made to develop a topological optimization approach for the preform design in bulk metal forming processes based on the bidirectional evolutionary structural optimization strategy. In this approach, a new strain-based element addition and removal criterion has been proposed for evaluating and optimizing the material flow in the forging process. To obtain a smooth preform boundary, a closed B-spline curve based on the least square algorithm is employed to approximate the uneven surface of the updated preform profile. A C# program has been developed to integrate the FE simulation, shape optimization, and surface approximation processes. Two 2D forging preform design problems are evaluated by using the developed method. The results suggest that the optimized preform with the strain uniformity criterion has shown better performance in improving the material flow and deformation uniformity during the forging process. The results also demonstrate the robustness and efficiency of the developed preform optimization method. 相似文献
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Fuh-Kuo Chen Tyng-Bin Huang Shin-Gee Chen 《The International Journal of Advanced Manufacturing Technology》2007,32(3-4):272-279
Embossment formation in press forging of AZ31 magnesium-alloy thin-walled structural components used in the electronics industry
was examined by both the finite element analysis and the experimental approach in the present study. The mechanical properties
of the AZ31 magnesium-alloy at elevated temperatures were first obtained from the compression tests under various strain-rates.
The compression test results suggest that a feasible press forging process of AZ31 magnesium-alloy needs to be conducted at
a forming temperature higher than 300°C. The ring compression tests were also performed at various temperatures to obtain
the friction factors at the die-blank interface under different lubrication conditions. The experimental results were then
employed in the finite element simulations to investigate the effects of process parameters, such as punch shape and sheet
thickness on the formation of embossments in a press forging process, and a modified punch shape was proposed to improve the
efficiency of embossment formation according to the finite element analysis. Experiments of press forging of AZ31 magnesium-alloy
sheets were conducted to validate the finite element analysis. Good correlations were observed between the finite element
simulation results and the experimental data in all respects. The experiments conducted in the present study not only validated
the finite element analysis but also confirmed the efficiency of the modified die design in helping the embossment formation.
The mechanical properties of AZ31 magnesium-alloy at elevated temperatures and the detailed examination of the material flow
on the formation of embossments made in the present study could provide a design guideline for a press forging process of
AZ31 magnesium-alloy sheets. 相似文献
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Multi-objective optimization of an axial compressor blade 总被引:2,自引:0,他引:2
Numerical optimization with multiple objectives is carried out for design of an axial compressor blade. Two conflicting objectives,
total pressure ratio and adiabatic efficiency, are optimized with three design variables concerning sweep, lean and skew of
blade stacking line. Single objective optimizations have been also performed. At the data points generated by D-optimal design,
the objectives are calculated by three-dimensional Reynolds-averaged Navier-Stokes analysis. A second-order polynomial based
response surface model is generated, and the optimal point is searched by sequential quadratic programming method for single
objective optimization. Elitist non-dominated sorting of genetic algorithm (NSGA-II) with ε-constraint local search strategy
is used for multi-objective optimization. Both objective function values are found to be improved as compared to the reference
one by multi-objective optimization. The flow analysis results show the mechanism for the improvement of blade performance. 相似文献
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Performance enhancement of axial fan blade through multi-objective optimization techniques 总被引:2,自引:0,他引:2
Jin-Hyuk Kim Jae-Ho Choi Afzal Husain Kwang-Yong Kim 《Journal of Mechanical Science and Technology》2010,24(10):2059-2066
This paper presents an axial fan blade design optimization method incorporating a hybrid multi-objective evolutionary algorithm
(hybrid MOEA). In flow analyses, Reynolds-averaged Navier-Stokes (RANS) equations were solved using the shear stress transport
turbulence model. The numerical results for the axial and tangential velocities were validated by comparing them with experimental
data. Six design variables relating to the blade lean angle and the blade profile were selected through Latin hypercube sampling
of design of experiments (DOE) to generate design points within the selected design space. Two objective functions, namely,
total efficiency and torque, were employed, and multi-objective optimization was carried out, to enhance the performance.
A surrogate model, Response Surface Approximation (RSA), was constructed for each objective function based on the numerical
solutions obtained at the specified design points. The Non-dominated Sorting of Genetic Algorithm (NSGA-II) with local search
was used for multi-objective optimization. The Pareto-optimal solutions were obtained, and a trade-off analysis was performed
between the two conflicting objectives in view of the design and flow constraints. It was observed that, by the process of
multi-objective optimization, the total efficiency was enhanced and the torque reduced. The mechanisms of these performance
improvements were elucidated by analysis of the Pareto-optimal solutions. 相似文献