汽车覆盖件内凹圆弧翻边仿真与变形控制研究

分析了汽车覆盖件圆弧曲面不光顺发生区域的几何特征,指出内凹型翻边是缺陷产生的原因.提取了内凹翻边的几何模型并利用板料成形仿真软件ETA/Dynaform对翻边成形过程进行仿真,结果表明,翻边时圆弧过渡区受周向的剪应力,这个剪应力是圆弧不光顺产生的诱因.通过改变翻边几何参数和工艺参数得到了这些因素对圆弧不光顺的影响规律,结果表明:随着动模圆角半径和翻边高度的增大,圆弧不光顺有加重的趋势;减小定模圆角半径、动定模间隙、翻边轮廓圆弧半径和摩擦系数可以改善圆弧不光顺.

Numerical simulation and deforming control of concave curvature flanging in automobile panels

By analyzing the geometry of the forming part, it is figured out that concave curvature flanging causes the uneven arris. The geometry of concave curvature flanging in fiat plane was abstracted and the flanging process was sim-ulated with sheet-metal forming FED codes ETA/Dynaform. Result shows that the circumferential shearing stress in the arris region causes the defect. Then the process parameters were studied and several rules were concluded that une-ven tendency increases with increasing radius of punch and the flanging height, while the defect can be reduced by de-creasing the radius of die, clearance , flanging contour curvature and the friction coefficient.