【作者】 田辉；

【导师】 周文龙；

【作者基本信息】 大连理工大学 ， 材料加工工程， 2010， 硕士

【摘要】 旋压成形可旋制无缝空心回转体零件,具有变形条件好、产品性能优、尺寸公差小、材料利用率高、产品类别广泛等优点,广泛应用于兵器、航空、航天、民用等金属精密加工技术领域。实际生产过程中影响产品质量的因素很多,各参数之间的合理搭配需要工艺人员在试生产中反复摸索调试。采用有限元数值模拟技术可以降低成本,提高生产效率,为工艺设计和实验研究提供指导。本文以筒形件外旋压和带内筋筒形件内旋压过程为研究对象,基于MSC.Marc元平台,建立了旋压成形过程的三维有限元模型,并分析了其成形机理及工艺参数对成形过程的影响规律。首先,根据有限元理论,毛坯采用六面体单元划分网格,对尾顶、芯模和旋轮进行了模型的离散化,并有效地解决了摩擦接触、边界约束与旋轮轨迹等关键问题。从而建立了合理的筒形件旋压成形有限元模型。基于上述模型,得到筒形件外旋压变形过程中应力场、应变场分布规律。探讨了旋压方式和工艺参数对旋压力及工件质量的影响。针对TC4钛合金的正旋压工艺,研究结果显示：随着减薄率、进给比和圆角半径增加,各方向旋压力均呈增大趋势,径向旋压力增加速率较大；增大成形角,总旋压力和径向旋压力显著减小,而轴向旋压力呈增大趋势。通过模拟,研究带内筋筒形件内旋压成形的基本规律及旋压力的变化趋势。分析了不同减薄率和进给比对金属流动、工件尺寸精度和内筋高度的影响。研究认为：随着减薄率增大,工件尺寸精度降低,内筋高度略有增大；当进给比在较小的范围(小于1.5mm/r)时,增大进给比,外径尺寸精度显著改善,而内筋高度明显减小。更多还原

【Abstract】 Spinning easily manufactures the product of seamless hollow rotary body. It has many advantages, including good deformation conditions, excellent product performance, precise dimensional tolerance, high material utilization ratio, great product categories and so on. It has been widely applied in weapons, aviation, astronavigation, civil and other metal precision forming technology departments. In the process of manufacture, many process parameters affect the qualities of spinned parts, engineers have to establish process parameters by trial-and-error approach. Finite element numerical simulation technology may reduce cost, increase production efficiency and provide a guide for the process design and experimental study.In this dissertation, outside spinning of tube and interior spinning of tube with inner rib are analyzed. Firstly,3D FEM models of these forming processes are established under MSC.Marc software environment, and then the deformation mechanism and the influencing laws of technological parameters are investigated.First, by means of finite element theory, the hexahedron element has been used for plotting the blank. Clamp, mandrel and roller have been discreted respectively. Some key technologies have been solved, including friction condition, boundary condition and roller path etc. Then, reasonable FEM models of spinning of tube are established.Based on the model established above, the distribution and variation features of the stress and strain during outside spinning of tube deformation have been obtained. The effects of spinning modes and technological parameters on spinning forces and workpiece quality have been analyzed. The results demonstrate that spinning forces increase with the increasing of reduction, feed rate and fillet radius, especially the radial spinning force. With the increasing of the forming angle, the total spinning force and radial spinning force decrease rapidly, but the axial spinning force increases slightly.Deformation law and variation tendency of spinning force have been researched during interior spinning of tube with rib by simulation. The influence of reduction and feed rate on metal flow, dimensional precision and height of the inner rib are studied. Researches show that with the increasing of reduction, dimensional precision decreases and the height of the inner rib enhances a little. With the increasing of feed rate, dimensional precision significantly improves, but the height of the inner rib reduces rapidly when feed rate is under 1.5 mm/r.更多还原