顶端板拉深回弹控制与影响因素分析

Control of drawing springback of top plate and analysis of influencing factors

针对某轨道客车顶端板拉深成形存在的缺陷，运用塑性力学理论进行应力分析，提出优化补充造型和翼边反向拉深的控制方法，并运用数值模拟分析不同因素对板料拉深回弹和翘曲的影响规律。结果表明，进行板料工艺补充、增加翼边拉深工序能有效地减小端壁翘曲和拱顶外张。增大板料大曲率半径段外扩量、增大压边力和减小凹模圆角半径能有效减小端壁翘曲回弹量。控制翼边顶料板圆角半径在R4～R8mm，凸、凹模间隙在1．6～2mm，翼边压边力小于3000kN都能有效地控制板料拉深回弹。

Plastic mechanics theory was applied to carry out stress analysis on the defects existing in the drawing of a rail passenger car top plate. The optimization of supplementa ry modeling and the control method of wing side reverse drawing were proposed; and then the influence law of different factors on the plate drawing springback and warping was ana lyzed by using numerical simulation. The result shows that the process supplement of plate and the addition of wing side drawing process can effectively reduce the endwall warping and vault extension; and the enlargement of outside expanding amount of large curvature radius section, the increase of blank holder force and decrease of cavity die fillet radius can effectively reduce the warping springback amount. The drawing springback of plate can be controlled effectively by controlling of the fillet radius of wing side ejector plate in R4-R8 mm, the punch and die clearance in 1.6-2 mm, and the blank holder force of wing side less than 3000 kN.