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汽车覆盖件刚度及控制 总被引:1,自引:0,他引:1
汽车覆盖件的刚度大小对汽车的安全性、驾驶室的工作环境及使用寿命有很大的影响。掌握影响覆盖件刚度的因素及影响规律,通过改善覆盖件的结构、板材在冲压成形中的塑性为形等措施,可以提高覆盖件的刚度。 相似文献
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汽车覆盖件的刚度大小对汽车的安全性、驾驶室的工作环境及使用寿命有很大影响。掌握影响覆盖件刚度的因素及影响规律,通过改善覆盖件的结构、板材在冲压成形中的塑性变形等措施,可以提高覆盖件的刚度。 相似文献
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为研究基于液压成形的汽车钣金件成形规律,以汽车中空异形板件为研究对象,自行设计并搭建板材液压成形实验测试系统,以此开展板件液压成形的实验研究,借助DYNAFORM有限元软件对板材液压成形进行有限元仿真分析,通过与实验测试结果的对比,验证了建立的有限元模型与数值模拟的正确性。以此为基础,探究压边力、压边力加载路径、液室压力、压边间隙和板材与凹模之间的摩擦系数等关键工艺参数对板材液压成形厚度的影响规律,提出汽车中空异形板件液压成形工艺,为板材液压成形技术在汽车钣金件成形中的应用提供参考。 相似文献
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In this article, the elastic-plastic finite element formulations using dynamic explicit time-integration schemes are proposed
for numerical analysis of automotive body panel stamping processes. A general formulation of finite element simulation for
complex sheet forming processes with arbitrarily shaped tools is briefly introduced. In finite element simulation of automotive
body panel stamping processes, the robustness and stability of computation are important requirements since the computation
time and convergency become major points of consideration besides the solution accuracy due to the complexity of geometry
and boundary conditions. For analyses of more complex cases with larger and more refined meshes, the explicit method is more
time effective than the implicit method, and it has no convergency problem and has the robust nature of contact and friction
algorithms, although the implicit method is widely used because of excellent accuracy and reliability. The elastic-plastic
scheme is more reliable and rigorous, while the rigid-plastic scheme requires short computation time. The performance of the
dynamic explicit algorithms is investigated by comparing the simulation results of forming of complex-shaped automotive body
parts, such as a fuel tank and a rear hinge, with the experimental results. It has been shown that dynamic explicit schemes
provide quite similar results to the experimental results. It is thus shown that the proposed dynamic explicit elastic-plastic
finite element method enables an effective computation for complicated automotive body panel stamping processes. 相似文献
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起皱和拉裂缺陷是汽车车身零件在拉延成形中常见的成形缺陷。为了控制拉延成形缺陷,以某汽车发动机盖内板件为研究对象,通过Autoform建立有限元模型,并借助Design-Expert进行实验设计。采用数值模拟软件和实验设计方法对汽车发动机盖内板件的拉延筋阻力系数和压边力参数进行优化。优化后的最优参数组合为:拉延筋的阻力系数大小分别为A=0.3,B=0.3,C=0.4,压边力大小D=1.25×10~3kN。采用优化后的参数进行实验,实验得到零件无拉裂和起皱缺陷,表明本文采用的方法可以有效地控制车身零件拉延成形中的缺陷。 相似文献
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板料冲压过程是一个非常复杂的塑性成形过程,许多因素都直接或间接影响着成形的结果.以Forge2D软件为平台,采用弹塑性有限元法对某一汽车轮毂零件的成形过程进行数值模拟,揭示零件冲压过程中板料的变形行为,预测冲压过程中可能出现的各种工艺缺陷,例如坯料的局部减薄和破裂,并以模拟结果为依据提出改进工艺参数的办法,优化工艺参数,可以减少调试和修模的次数,以此实现降低模具费用、缩短制模时间、提高产品成品率和材料利用率,最终达到减少产品成本的目的.在此基础上,对3种冲压工艺方案分别进行了数值模拟,对比研究了各方案的成形特点,得出了较好的成形工艺参数方案. 相似文献
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用动态显式有限元法对板材成形进行计算机模拟 总被引:14,自引:1,他引:13
介绍了动态显式有限元法的原理和特点 ,总结讨论了国际现有各种商用有限元软件的情况。采用显式有限元软件 L S- DYNA3D对板材零件冲压过程进行计算机模拟分析 ,预测冲压过程中可能出现的各种工艺缺陷 ,例如坯料的起皱、局部减薄和破裂 ,并以模拟结果为依据提出改进模具和工艺参数的办法 ,优化工艺参数 ,可以减少调试和修模的次数 ,以此实现降低模具费用、缩短制模时间、提高产品成品率和材料利用率 ,最终达到减少产品成本的目的。 相似文献
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基于有限元分析的汽车覆盖件模具设计及优化 总被引:18,自引:3,他引:15
介绍了静力隐式弹塑性有限元板料成形软件AutoForm的基本理论和关键技术。利用AutoForm软件实现了汽车覆盖件模具设计,包括模具压料面、工艺补充面以及拉延筋设计,完成了覆盖件成形过程模拟及优化,改变了传统的在有限元模拟后依靠CAD软件频繁进行模具修改的方法。在有限元软件内部实现了模具的参数化设计,既缩短了模具设计时间,又提高了模具设计可靠性。 相似文献
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Crashworthiness (or collision performance) is a critical design factor in optimizing automotive part products. In this study,
a numerical sensitivity analysis was performed to investigate the effects of material properties on crashworthiness for automotive
sheet materials. As standard material parameters, the measured mechanical properties of AA 6111-T4 sheet were considered,
based on the anisotropic non-quadratic yield function, YId2004-18p, and a combination type non-linear isotropic-kinematic
hardening law. The constitutive law was implemented into codes of the commercial finite element program ABAQUS, using user
material subroutines. As for process simulations, spring-back after forming as well as sheet forming and collision were included
in this evaluation. 相似文献
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数值模拟技术作为一种重要的有限元技术,广泛应用与各种工业领域,在汽车制造业中显得由为重要。介绍了基于Jstamp/NV的数值模拟技术在汽车制造业中的重要地位及应用情况,并以行李箱盖内板、横梁、挡泥板和B-柱为实例,分别概述了Jstamp/NV高精度的回弹预测功能、回弹补偿功能和油石仿真功能的应用。利用Jstamp/NV,通过对几种典型汽车车身件的仿真分析,证实了数值模拟技术能够准确地预测汽车车身件在冲压成形过程中经常出现的回弹及凹坑等缺陷,并指出数值模拟技术在冲压成形中正发挥着越来越重要的作用。 相似文献
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G. Giuliano S. Franchitti 《International Journal of Machine Tools and Manufacture》2007,47(3-4):471-476
In recent years, there has been a considerable interest in the application of superplastic forming in the aircraft and automotive industries to realize complex parts. This requires a detailed design of the technological process in order to better exploit its peculiar potentialities. Nowadays, the finite element method represents the mainly used technique to plan the sheet metal forming processes whose simulation requires determination of material constants for superplastic materials. The aim of the present work is aimed to show a simple method to characterize superplastic materials. In this study, constant pressure free bulging for superplastic materials is analysed by finite element method and expressions to determine the constants of the superplastic materials have been proposed. In order to support the proposed method, numerical and experimental activities have been carried out which show the good reliability of values obtained from proposed expressions. 相似文献