Effect of pre-forming and pressure path on deformation behavior in multi-pass hydrodynamic deep drawing process
Effect of pre-forming and pressure path on deformation behavior in multi-pass hydrodynamic deep drawing process
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预成形和压力路径对多道次流体动力拉深过程变形行为的影响
DOI：
10.1016/j.ijmecsci.2017.01.010
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发表时间：
2017-02
影响因子：
7.3
通讯作者：
Min Wan
中科院分区：
文献类型：
--
作者：
Weidong Li;Bao Meng;Chu Wang;Min Wan
充液拉深成形是一种加工深型腔复杂曲面零件的有效方法。尽管单冲程HDD工艺的发展已经取得了显着的进步，但由于独特的工艺分配和连续变形行为，多级HDD技术中的一些基本挑战仍然没有解决。研究了预成形参数和型腔压力加载轨迹对铝合金连续变形的影响，确定了多道次HDD成形深型腔锥形件的适宜工艺条件。基于等容差函数法，对多道次成形的材料变形量进行了分配和优化。此外，还讨论了多步工艺过程中出现的裂纹和撕裂等缺陷模式。分析了预成形深度和型腔压力加载轨迹对工件尺寸精度和厚度变化的影响，采用不同屈服准则的数值模型，得到了合适的预成形深度和型腔压力加载轨迹。结果表明，yld 2000 -2d和BBC 2005屈服函数相对于Mises各向同性公式和Hill'48屈服准则能更准确地预测预成形深度。然而，由于误差累积和预应变对后续过程的影响，使用yld 2000 -2d屈服公式对预成形阶段的预测精度优于最终成形阶段的预测精度上级。此外，中间圆柱形件的合理型腔压力加载路径具有3个特征点，而最终圆锥形件的压力轨迹具有4个唯一点和3个明显的分段，即低压阶段、升压阶段和全压阶段。在合适的工艺条件下，成形出了厚度分布均匀、表面光洁度好、尺寸精度高的锥形件，表明多道次HDD成形技术适用于复杂形状、高拉深比零件的一体化精密成形。
Hydrodynamic deep drawing (HDD) is an effective method for the fabrication of the sheet metal parts with deep cavity and complex surface configuration. Despite the remarkable progress that has been made on the development of one-stroke HDD process, a number of fundamental challenges are still unsolved in the multi-stage HDD technology due to the unique process allocation and continuous deformation behavior. In this study, the effect of pre-forming parameters and loading locus of cavity pressure on the sequential deformation of aluminum alloy is explored to determine the suitable working conditions to form a conical part with deep cavity using multi-pass HDD process. Based on the equal allowance function method, the material deformation amount for the multi-pass process is allocated and optimized. In addition, the defect patterns including wrinkling and tearing during the multi-step process are discussed. The effect of pre-forming depth and loading loci of cavity pressure on the dimensional accuracy and thickness variation of the workpiece is analyzed, the appropriate pre-forming depth and loading loci of cavity pressure are achieved by using numerical models implementing diverse yield criteria. The results mirror that yld2000-2d and BBC2005 yield functions predict the pre-forming depth more accurately with respect to Von Mises isotropic formulation and Hill’48 yield criterion. However, the prediction accuracy of the pre-forming stage is superior to that of the final forming period using yld2000-2d yield formula due to the error accumulation and the effect of prestrain on the sequential process. Moreover, the reasonable loading path of cavity pressure for the intermediate cylindrical part is characterized by three feature points, whereas the suitable pressure locus for the final conical part is featured with four unique points and three distinct segments containing low-pressure stage, pressure-raising stage and full pressure period. By using the suitable working conditions, the well-formed conical part with homogenous thickness distribution, desirable surface finish, and high dimensional precision is fabricated, which highlights that the proposed multi-step HDD technology is valid for the integration and precision forming of the workpiece with complex feature and high drawing ratio.
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影响因子：
2.4
作者：
M. Tolazzi
通讯作者：
M. Tolazzi
DOI：
10.1016/s1003-6326(15)63934-6
发表时间：
2015-09
影响因子：
4.5
作者：
A. Hashemi;M. H. Gollo;S. Seyedkashi
通讯作者：
A. Hashemi;M. H. Gollo;S. Seyedkashi
影响因子：
5.7
作者：
B. Meng;M. Wan;X. D. Wu;Sheng Yuan;Xudong Xu;Jie Liu
通讯作者：
B. Meng;M. Wan;X. D. Wu;Sheng Yuan;Xudong Xu;Jie Liu
影响因子：
7.3
作者：
B. Meng;M. Wan;Sheng Yuan;Xudong Xu;Jie Liu;Zhenbiao Huang
通讯作者：
B. Meng;M. Wan;Sheng Yuan;Xudong Xu;Jie Liu;Zhenbiao Huang
影响因子：
6.3
作者：
H. Shim;Dong-Yol Yang
通讯作者：
H. Shim;Dong-Yol Yang