共查询到20条相似文献,搜索用时 78 毫秒
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摘 要:利用有限元数值模拟分析了各工艺参数(拉深温度、凸模圆角半径及凹模内圆角半径)对镁合金AZ31盒形件拉深成形性能的影响,并通过实验进行了验证.结果表明:采用最佳拉深温度和最佳的凸模圆角半径、凹模内圆角半径可以有效地改善厚度为0.5mm的镁合金AZ31板材的拉深成形性能. 相似文献
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汽车覆盖件成形过程的数值模拟 总被引:1,自引:2,他引:1
在汽车覆盖件成形过程中,预测与防止起皱现象的产生是极其重要的。本文采用了动力显式有限元算法,在实例分析的基础上,针对覆盖件坯料拉深过程中可能出现的起皱现象,给出相应的工艺和模具优化方案。 相似文献
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矩形盒深拉深成形有限元模拟 总被引:1,自引:5,他引:1
针对矩形盒成形过程中各种形式的起皱和拉裂问题,采用MSC.Marc有限元分析软件对矩形盒深拉延成形过程进行模拟。建立了包括板料、凸模、凹模及压边圈在内的整体分析模型,通过对成形过程中拉深件的等效应力进行比较,分析了不同的凸模圆角半径、凹模圆角半径及凸模角半径对矩形盒拉深成形的影响。此外,还对模拟结果做了进一步的分析,得出了凸凹模圆角半径之间的相应关系,以便合理的确定矩形盒深拉延成形时二者的取值范围。考察了模拟方法的可行性和可靠性。 相似文献
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本文基于连续介质力学及有限变形理论 ,建立了用于三维板料成形过程分析的有限元模型 ,开发了动力显式算法的板料成形过程模拟的有限元分析程序DESSFORM3D。采取集中质量矩阵 ,用动力显式积分的方法 ,使位移计算显式化 ,避免了由材料、几何、边界条件等高度非线性因素引起的计算收敛问题。对半球形凸模拉深过程进行模拟计算 ,并把模拟结果与实验结果进行对比 ,验证了软件的计算结果 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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The finite element formulation for predicting strain distributions and weld line movements in the forming processes of tailored
sheet metals is developed. The material properties of the welding zone such as strength coefficient, work-hardening exponent,
and plastic anisotropic parameter are analytically obtained from those of base metals based on the tensile tests. The welding
zone is modelled with the several, narrow finite elements called by weld elements. To verify the finite element formulation
for tailored blanks, the forming processes of autobody door inner panel section and hemispherical dome are simulated. FEM
predictions are compared and showed good agreements with experimental measurements. 相似文献
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采用弹塑性大变形更新的Lagrange有限元方法研究了铝板 /塑料混合成型过程中铝板的成形过程和变形特点。结果表明 ,当塑料熔体压力从 30MPa增大到 5 0MPa时 ,铝板凸缘区已基本不再参与变形 ,铝板上两个板厚减薄较严重的大塑性变形区在此阶段形成。模底接触区与自由变形区交界处的大塑性变形区依次处于板料曲面内双向伸长变形和平面应变状态 ;模腔入口圆角区与自由变形区交界处的大塑性变形区由两部分构成 ,其中与模壁接触部分依次处于板料曲面内双向伸长变形、拉伸变形和平面应变状态 ,另一部分依次处于板料曲面内双向伸长变形和平面应变状态。 相似文献