共查询到20条相似文献,搜索用时 31 毫秒
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相比板状扭力梁,采用液压成形工艺加工管状扭力梁能够减轻零件重量,提升零件强度、刚度和疲劳性能。分析了管状扭力梁零件的典型截面形状,指出了零件加工难点和成形过程中的主要缺陷。利用有限元仿真分析方法对管状扭力梁成形过程进行数值模拟,分析了成形过程中典型截面的壁厚变化规律,即过渡区域壁厚变化较大,中间区域壁厚变化不明显。在此基础上进行工艺试验。研究结果表明,管状扭力梁液压成形有限元仿真结果与试验结果吻合性好,零件的实际形状与理论设计形状基本一致。 相似文献
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对江淮SRV前梁液压胀形过程进行了数值模拟研究,应用弹塑性有限元动力显式分析程序LS-DY-NA进行求解分析.重点针对管坯初始尺寸的确定和内压加载路径的选择,给出了模拟结果.分析表明选择合适的管径和内压加载路径能改善成形过程中材料的流动、提高材料的成形极限、有利于产品质量的提高,模拟结果为工程应用提供了依据. 相似文献
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The material behavior of two different types of paperboard was characterized in tensile tests and in a new test device called paperboard bulge test. A particularly adapted hydroforming process was used to produce three-dimensional paperboard structures. Furthermore, an online measurement device to describe the mold-filling behavior is introduced. The experimental results were compared to the results obtained with an FEA investigation. The investigations showed the possibilities of the new forming process, as well as the advantages of FEA methods used to pre-define the process parameters. 相似文献
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A study on the analytical modeling for warm hydro-mechanical deep drawing of lightweight materials 总被引:3,自引:0,他引:3
Ho Choi Muammer Ko Jun Ni 《International Journal of Machine Tools and Manufacture》2007,47(11):1752-1766
The warm hydroforming process has become an emerging technology in recent years to reduce the weight of automotive body structure and minimize the number of process steps. In this study, analytical models were developed to investigate the effects of process conditions such as temperature, hydraulic pressure, blank holder force and forming speed. The analytical model under hydro-mechanical deep drawing (HMD) condition was developed based on experimental results in the literatures. FE models were also developed to validate the analytic models. Then, the analytic model was validated through comparisons with both existing experimental results and FE results. The analytical model provided rapid and reasonably accurate results for the design of warm hydroforming process. Based on this analytic model, several parametric studies were performed regarding to the temperature, hydraulic pressure, blank holder force, and punch speed conditions. It was demonstrated that the process windows for a successful part forming could be rapidly predicted with a reasonable accuracy by the analytic model compared to lengthy and costly thermo-mechanical FEA or experimental trial and error. 相似文献
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Modern lightweight construction, especially in the automotive industry, requires more and more complex components, which can be manufactured in one process step using the hydroforming technology. The combination of the tube and double sheet hydroforming is a new forming process, where a tube and two blanks are formed simultaneously in a die cavity, combining the advantages of both hydroforming variants. This paper deals with the fundamental considerations and investigations related to connection between tube and double sheet. The finite element analysis and laboratory trials were used in order to design the shape of the die cavity and to avoid wrinkles, material tearing and the collapse of the tube section during forming. The paper will also illustrate an analytical model for the prediction of the edge shape in the constrained bulging of a rectangular cup together with several technical solutions, which enabled a complete forming of the investigated part. Finally, the definition of a hydroforming material factor based on the analytical model of the hydraulic bulging process enables the right choice of sheets with different material strength and thickness for the hydroforming of hybrid components. 相似文献
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欧洲管材内高压成形和板材液压成形研究现状(英文) 总被引:1,自引:1,他引:1
在欧洲,管材、型材以及板材的液压成形是密切相关的。液压成形产品主要是用于汽车工业批量生产的零件以及一些有独特用途的零件,其市场仍然在逐渐增长。目前轻量化制造、新型零件的高度功能集成化以及关于使用内高压件的不断积累的设计经验、理念,正影响着液压成形新技术的开发。由于可观的利润率,开放截面和闭合截面的铝合金型材的液压成形件正在试制,并在此背景下,开展了一些专用车面板的液压成形技术开发。这个利润率,将从半成品零件、成形中间过程,直到最终总成件整个工艺链来计算。从管材和板材的液压成形件来看,提高液压成形模具的功能集成性也是必须要做的工作。文章作者就内高压成形的模具设计以及功能集成给出了解决方案,并进一步讨论了内高压成形工艺的利润率。 相似文献
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Optimized constitutive equation of material property based on inverse modeling for aluminum alloy hydroforming simulation 总被引:2,自引:2,他引:0
Li-hui LANG Tao LI Xian-bin ZHOU B.E. KRISTENSEN J. DANCKERT K.B. NIELSEN 《中国有色金属学会会刊》2006,16(6):1379-1385
1Introduction Sheet hydroforming has many advantages such as high drawing ratio,good part surface,and can be applied widely in the versatile and low volume production with miscellaneous materials such as aluminum alloys,high-strength steel,stainless steel… 相似文献
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类似汽车横梁这些复杂管类结构件的充液成形,是一个不均匀的变形过程,坯料的相对形状及尺寸,是影响金属流动的关键因素,从而对充液成形零件的最小壁厚、最大壁厚等评价对象有重要影响。以坯料的弯曲角度、弯曲半径、轴线高度差为因子,建立正交试验设计方案,进行有限元模拟,获得不同坯料尺寸下的最小壁厚、最大壁厚参考序列。利用灰色系统理论,计算各个参考序列与比较序列之间的关联系数,将多目标转化为以关联度为目标的单目标。进一步计算各坯料结构尺寸的平均关联度,获得优化的坯料尺寸组合参数,以此进行有限元模拟和生产实验。验证结果表明,该优化方法能够获得满足质量要求的充液成形的汽车横梁。 相似文献
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In this study, a methodology is developed to determine proper profiles of the hydraulic pressure and the blank holder force under warm hydroforming conditions at different punch speeds. First, finite element models (2-D and 3-D) are developed and validated through comparisons with the experimental results from the literature. To determine the optimal hydraulic pressure and blank holder force profiles simultaneously, an adaptive FE analysis with fuzzy control algorithm was developed. Thinning, wrinkling, punch wall contact, die corner floating and conduction were used as criteria in the fuzzy control algorithm. The effects of the determined loading profiles are then presented in terms of thickness, strain and stress, and temperature distributions as well as success/failure of the forming process. The effect of punch speed was also investigated to reveal its impact on part formability. It was found that the optimal process conditions can be rapidly and accurately obtained with the developed adaptive FEA method coupled with fuzzy control algorithm. 相似文献
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空心双拐曲轴内高压成形数值模拟 总被引:1,自引:0,他引:1
应用动态显式有限元法对空心双拐曲轴的内高压成形过程进行了模拟分析,研究了加载路径对内高压成形的影响,指出了在加载曲线中存在着最佳成形区间,成形压力小于20MPa时,管坯产生起皱,成形压力大于32MPa时,管坯发生开裂,只有合理的应用加载路径,成形压力介于20MPa与30MPa之间,使轴向进给量可以正好补偿径向的变形量才能获得壁厚较为均匀的合格零件。 相似文献
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智能与控制在塑性加工制备与成形中的应用 总被引:2,自引:0,他引:2
对材料制备与塑性加工方面的智能控制特点进行了介绍与分析。首先对钢铁、铜及铜合金管材连铸连轧过程控制加工特点进行了阐述 ,其次介绍了镁合金的“轧制 等通道角挤压 拉制”连续加工制备技术和镁合金薄板半固态双辊铸轧工艺。对于薄板增量加工成形技术 ,介绍了飞机整体壁板增量压弯技术、薄板单点无模增量成形技术和多点无模增量成形技术。讨论了薄板可动凹模液压成形技术、异型截面管件液压成形技术和细长杆件空间弯扭成形技术原理。最后对于微小件加工技术进行了简要介绍 相似文献
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为有效地预测管材液压成形过程中存在的问题,比如:制件在外侧过度减薄和内侧起皱,用JSTAMP/NV对汽车副车架液压成形工艺过程进行有限元模拟分析,得出各工序的仿真结果。应用逆向求解器Hystamp仅需直接指定管坯的尺寸参数、材料和弯曲工艺参数即可自动执行弯曲仿真计算并可在几秒内获取弯曲仿真的结果;应用LS—DYNA执行预成形和液压成形工序仿真的计算,需设定液压成形工序的工艺参数,包括液压加载的曲线和方向以及轴向进给位移。JSTAMP/NV能有效模拟管材液压成形工艺过程并预测成形过程中在变形区出现的屈曲、起皱和破裂等缺陷,可以为工艺试验提供指导。 相似文献
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Feifei Zhang Jun Chen Jieshi Chen Jian Lu Gang Liu Shijian Yuan 《Journal of Materials Processing Technology》2012,212(11):2228-2237
The hydroforming process is used widely across many industrial fields. High applied pressure during hydroforming makes it necessary to consider the influence of the through-thickness normal stress, while traditional approaches based upon a plane-stress assumption are not appropriate in such cases. Reliable constitutive models that consider the through-thickness normal stress are summarized in this paper, which focuses on the state of the art in the following several aspects: determine the flow stress curve with proper experimental methods and choose the measurement and computational methods to minimize the error as much as possible; select the proper three-dimensional anisotropic yield criterion for the specific material; Define the forming limit model and construct corresponding experimental verification method. The review of existing work has revealed several gaps in current knowledge of the hydroforming process accounting for the through-thickness normal stress. Conclusions are drawn concerning some critical issues and potential future developments in hydroforming modeling. 相似文献
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A comparative study of stamping and hydroforming processes for an automobile fuel tank using FEM 总被引:1,自引:0,他引:1
Beom-Soo Kang Bo-Mi Son Jeong Kim 《International Journal of Machine Tools and Manufacture》2004,44(1):87-94
The use of sheet metal in the hydroforming process for hollow bodies is a new manufacturing technology for the automotive industry. In this paper, a comparison is made between the forming processes of sheet hydroforming and conventional stamping for production of an automobile fuel tank using a commercial explicit FEM code. A modeling methodology for correlation between stamping and hydroforming is proposed in order to obtain the optimal process parameters for producing a sound hydroformed fuel tank. The simulation model for a conventional stamping process is also verified by comparison with experiment. Finally, it is concluded that the hydroforming process can produce a fuel tank with a more uniform and sound thickness distribution than the stamping operation. 相似文献