基于不同减薄量的纵向内筋薄壁筒反向滚珠旋压分析

Analysis on backward ball spinning of the thin-walled tube with longitudinal inner ribs based on various wall thickness reductions

采用反向滚珠旋压制造带有纵向内筋的薄壁筒形件.将刚塑性有限元与工艺实验相结合,被应用于分析在不同壁厚减薄量下带有纵向内筋薄壁筒形件反向滚珠旋压成形.有限元模拟结果和实验结果都表明内筋的高度随着壁厚减薄量的增加而增加,但在模拟结果与实验结果之间存在着大约10%的误差.有限元模拟的应变等值线图表明在筒壁变形区的径向应变和内筋变形区的切向应变有助于内筋的成形.轴向旋压力有限元预测结果表明较大的壁厚减薄量导致了轴向旋压力的增加,同时也导致了旋压件表面金属材料的非稳定流动.

Backward ball spinning was applied to manufacturing the thin-walled tube with longitudinal inner ribs. Rigid-plastic finite element method （FEM） along with the process experiments was used to analyze backward ball spinning of the thin-walled tube with longitudinal inner ribs under various wall thickness reductions. Finite element simulation results and experimental results indicate that the height of the inner ribs increases with the increase of wall thickness reduction, but there exists a difference of about 10% between the simulation results and the experimental ones. The strain contour charts from FEM show that the radial strain in the deformation zone of the tubular wall and the tangential strain in the deformation zone of the inner rib contribute to forming the inner rib However, the axial strain has an adverse influence on forming of the inner ribs. The FEM prediction results of the axial spinning force component reveal that the larger wall thickness reduction leads to the increase of the axial spinning force component as well as the unsteady flow of the metal on the surface of the spun part.