汽车围板冲压成形研究

发布时间：2018-04-25 03:41

本文选题：汽车围板 + 拼焊板　；参考：《沈阳理工大学》2015年硕士论文

【摘要】：汽车轻量化是最近几年的研究热点。传统的汽车覆盖件的成形方法分为分离成形法和整体成形法。前者的特点为模具较多,工艺复杂,后者的工艺简单但增加了车身的重量。拼焊板避免了两者的缺点,同时达到轻量化的目的。拼焊板是将不同厚度和力学性能的两块或以上板材通过焊接的方法得到所需要的板材,但拼焊板增大了成形时的难度。大量研究表明焊缝对拼焊板成形能力有较大影响。本文从工艺补充造型、压边力大小、焊缝位置、拉延筋这几个方面进行分析,控制焊缝的移动,防止成形缺陷的发生,从而得到合格的拉延零件。本文应用AUTOFORM软件进行汽车围板拉延成形的数值模拟分析。对围板三维模型进行工艺补充时,首先选取无冲压负角的冲压方向,而后进行内工艺补充和外工艺补充。最终选定用拉延阻力最大的特征截面线来生成工艺补充面。制作完工艺补充后,在AUTOFORM中对拉延工艺参数进行模拟。首先利用一步法反计算毛坯的大小,对材料为DC04,厚度为0.8mm的板材拉延成形进行模拟分析,得出合理的压边力大小,为拼焊板做基础。选定材料为DC04/B280vk,厚度为0.8/1.2mm的拼焊板的拉延过程进行模拟分析,主要从焊缝位置和压边力大小两方面做了研究。当焊缝处于中心位置时正好位于变形最剧烈的位置,成形性不理想。将焊缝位置移动20mm后,选定压边力为450KN时,模拟结果表明成形效果较理想。根据模拟所得到的虚拟拉延筋参数可得到真实拉延筋参数,用UG软件设计真实拉延筋,重新模拟,得到更加接近实际的结果。用UG制作汽车围板的拉延成形模具三维模型,加工拉延模具,根据模拟得出的工艺参数,进行实验验证。试冲结果较理想,实验结果和模拟结果相一致,验证了模拟结果的正确性。拉延完成后,经过冲孔、侧冲孔、切边、修边、翻边、整形后得到最终成品零件。
[Abstract]:Automobile lightweight is a hot research topic in recent years. The traditional forming method of automobile panel is divided into separate forming method and integral forming method. The former is characterized by more molds and complex processes, while the latter is simple but increases the weight of the body. The TWBS avoids the disadvantages of both and achieves the goal of lightweight at the same time. Two or more plates with different thickness and mechanical properties are used to obtain the required plates by welding method, but the TWBs increase the difficulty of forming. A large number of studies show that the weld has a great effect on the forming ability of TWF. In this paper, the process supplementary modeling, the size of the blank holder force, the position of the weld seam and the drawing bar are analyzed to control the movement of the weld seam and prevent the forming defects, so as to obtain the qualified drawing parts. In this paper, AUTOFORM software is used to simulate and analyze the drawing forming of automobile coaming plate. In the process supplement of 3D model of coaming plate, the stamping direction without negative angle of stamping is first selected, and then the internal process supplement and external process supplement are carried out. Finally, the feature cross section line with the largest drawing resistance is selected to generate the process supplementary surface. After finishing the process supplement, the drawing process parameters are simulated in AUTOFORM. First, the blank size is calculated by one step method, and the sheet metal drawing forming with DC04 material and 0.8mm thickness is simulated and analyzed, and the reasonable blank holder force is obtained, which is the foundation of the TWBS. The drawing process of TWB with thickness of 0.8/1.2mm is simulated and analyzed by using DC04 / B280vkk material, which is mainly studied from two aspects: the position of weld seam and the size of blank holder force. When the weld is in the center position, it is in the most deformed position, and the formability is not ideal. The simulation results show that the forming effect is satisfactory when the position of weld is moved to 20mm and the blank holder force is chosen as 450KN. According to the virtual drawing bar parameters obtained by simulation, the real drawing bar parameters can be obtained, and the real drawing bars are designed by UG software. The simulation results are closer to the actual results. The 3D model of drawing forming die of automobile coaming plate was made by UG, and the drawing die was processed, and the experiment was carried out according to the process parameters obtained by simulation. The experimental results are in good agreement with the simulation results, and the correctness of the simulation results is verified. After drawing, through punching, side punching, cutting, trimming, flanging, shaping to get the final parts.
【学位授予单位】：沈阳理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U466;TG379

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