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基于数值模拟的铝型材挤压变形规律的研究(I) 总被引:1,自引:0,他引:1
采用有限变形弹塑性有限元方法 ,以型材挤压过程的有限元模拟为基础 ,研究了局部挤压比、挤压带面积和模孔距离对金属流动速度的影响 ,获得了型材挤压过程的一般变形规律。 相似文献
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采用有限体积法,对异形空心铝合金型材挤压过程进行数值模拟,得到了挤压过程中材料流动速度场、应力场、应变场、温度场和挤压力的分布规律。以数值模拟结果为依据,针对模具设计存在的问题提出了解决方案,并通过分析得到了模具的最佳设计方案。结果表明:对于薄壁、结构复杂的异型空心型材,挤压模具设计的关键是合理地分配金属流量和平衡金属的流动速度。 相似文献
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对铝质齿轮进行挤压模设计,建立有限元分析模型,获得挤压金属的稳态流动情况,分析速度分布、应力分布和出口位移分布;针对数值模拟结果,对模具提出修改意见,通过修改上模块工作带和下模增加阻流圈的方案,最终加工出来的模具可以生产出合格的产品。 相似文献
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Cunsheng Zhang Guoqun Zhao Hao Chen Yanjin Guan Haijin Cai Baojie Gao 《Journal of Materials Engineering and Performance》2013,22(5):1223-1232
Currently, with the increasing demand of high production output, much attention is paid to the research and development of multi-hole extrusion die. However, owing to the complexity of multi-hole porthole extrusion technology, it has not been applied widely in practice for the production of aluminum profiles, especially for porthole die with an odd number of die orifices. The purpose of this study is to design a three-hole porthole die for producing an aluminum tube and to optimize the location of die orifices based on computer-aided design and engineering. First, three-hole extrusion dies for different locations of die orifices are designed. Then, extrusion processes with different multi-hole porthole dies are simulated by means of HyperXtrude. Through numerical simulation, metal flow, temperature distribution, welding pressure, extrusion load, and die stress, etc. could be obtained, and the effects of the location of die orifices on extrusion process are investigated. With the increasing distance between die orifice and extrusion center (described as eccentricity ratio), metal flow becomes nonhomogeneous, and twisting or bending deformation of profile occurs, but the welding pressure rises, which improves the welding quality of profiles. However, the required extrusion force, billet and die temperature, die displacement, and stress induce no significant changes. In comparison with the extrusion force during single-hole porthole extrusion, there is 18.5% decrease of extrusion force during three-hole porthole extrusion. Finally, design rules for this kind of multi-hole extrusion dies are summarized. 相似文献
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铝材长方形空心管挤压过程数值模拟与模具结构优化设计 总被引:3,自引:0,他引:3
对AA1100铝材长方形空心管的挤压过程使用数值分析软件SuperForge进行数值模拟。在挤压生产中,金属流出工作带时的流速均匀性是得到高质量型材的关键。在挤压生产中通常采用几种方法修改模具,消除流速不均,例如修改分流孔的大小、形状和位置分布,修改工作带长度和焊合室形状尺寸等。本文通过数值模拟发现在长方形空心管挤压的初始模具设计中型材截面流速不均匀,造成端面不平。对此,提出了三种模具修改方案,并分别对其进行了数值模拟,经过分析比较确定了最佳模具设计方案,由此方案可以生产出合格的挤压件。 相似文献
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According to the rigid-viscoplasticity finite element method, the porthole die extrusion process of an aluminum harmonica-shaped tube was successfully simulated based on software Deform-3D. The distribution of stress field, effective strain field, velocity field and temperature field during the extrusion process were discussed and the metal flow in welding extrusion was analyzed. The simulation results show that the material flow velocities in the bearing exit are non-uniform with the originally designed die and the forepart of the profile is not neat or even. Aiming at solving this problem, the modification method of die structure was improved. The result shows that the uniform material flow velocities in the die exit and a perfect extruded are obtained by modification bearing length. 相似文献
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To avoid distortion of complex extrudate profiles, it is essential that the exit velocity of the metal is uniform. The most important design parameter that controls the exit velocity is bearing length. However, this factor is not sufficient to achieve optimal design settings. This paper proposes an innovative layout design approach using a geometry based bearing length design methodology to minimise variations in exit velocity. This paper focuses on single hole extrusion dies and develops an optimisation algorithm suitable for any die profile. Since the optimised die design produces less bearing length difference, more uniform exit velocity and higher design quality would be achieved using the proposed approach. 相似文献
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分流组合模挤压铝合金口琴管的数值模拟 总被引:2,自引:1,他引:1
采用刚粘塑性有限元法,在DEFORM-3D有限元商业软件上成功实现了铝合金口琴管分流组合模挤压过程的三维数值模拟,获得了分流组合模挤压过程中材料的流动规律,挤压力、应力场、应变场和温度场的分布,以及模具出口处金属流速的分布情况。通过数值模拟发现,型材出口流速不均匀,造成端面不齐,对此,提出了模具修改方案,通过调节模具工作带的长度,实现了型材挤压出口流速均匀的目的,从而保障了型材的产品质量。模拟结果为模具的优化设计及工艺参数的选取提供了理论参考。 相似文献
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散热器铝型材挤压的数值模拟 总被引:1,自引:0,他引:1
采用基于A-L-E算法的HyperXtrude软件,建立有限元分析模型,对散热器铝合金型材挤压过程进行了稳态流动仿真,获得了型材的位移分布和速度分布图,模拟结果与生产实际吻合较好;针对试模出现的问题,对出口速度分布和应力分布进行分析,提出在下模增加阻流台和修改工作带方案,有效地解决了初始模具设计中速度分布不均的问题;最后针对装配后型材平面度达不到要求这一缺陷,对模具工作带进行调整优化,用优化后的模其生产的型材可以装配使用. 相似文献
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双孔模型材挤压过程的有限元分析 总被引:2,自引:0,他引:2
本文采用大变形弹塑性有限元理论 ,对双孔模型材挤压成形过程进行了有限元分析。模拟了双孔模非对称角铝型材挤压变形过程 ,获得了挤压变形时网格畸变、流速、应力和应变分布 ,展示了型材挤压件变形不均匀细节。并与单孔模型材挤压过程进行了比较 ,发现双孔模[1] 挤压时 ,变形体内存在两个互为相反方向的涡流场 ,它们相互抵消 ,从而可以消除型材挤压过程中产生的扭拧、波浪、弯曲等缺陷。为提高挤压件质量 ,优化设计多孔型材挤压模以及制定合理的工艺 ,提供了理论依据 相似文献
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To solve the defects of bottom concave appearing in the extrusion experiments of complex hollow aluminium profiles, a 3D finite element model for simulating steady-state porthole die extrusion process was established based on HyperXtrude software using Arbitrary Lagrangian–Eulerian (ALE) algorithm. The velocity distribution on the cross-section of the extrudate at the die exit and pressure distribution at different heights in the welding chamber were quantitatively analyzed. To obtain an uniformity of metal flow velocity at the die exit, the porthole die structure was optimized by adding baffle plates. After optimization, maximum displacement in the Y direction at the bottom of profile decreases from 1.1 to 0.15 mm, and the concave defects are remarkably improved. The research method provides an effective guidance for improving extrusion defects and optimizing the metal flow of complex hollow aluminium profiles during porthole die extrusion. 相似文献
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基于DEFORM3D模拟软件,针对连续挤压包覆过程中模腔流动通道长度和挤压轮转速对铝护套产品的影响进行有限元模拟分析,并进行实验验证。结果表明,模腔中流动通道长度对改善金属流动的均匀性、产品的弯曲角度和横截面的椭圆度发挥重要的作用,增加流动通道长度,可以使产品的流动速度变得均匀,产品的弯曲角度接近理想的零值,并可以获得良好的截面形状;当使用较长的流动通道时,挤压轮转速对产品的弯曲角影响不大。 相似文献