大高径比凸台缩径—冷镦成形工艺方案研究

Research on Necking and Cold Upsetting Process for Large Ratio of Height to Diameter Boss

针对大高径比凸台冷镦粗成形易出现失稳的问题,制定出缩径预成形、冷镦终成形的工艺方案。并通过Deform-3D软件模拟了缩径和冷镦成形过程,研究了坯料直径和入模半角对成形质量及成形力的影响。数值模拟结果表明,采用缩径—冷镦工艺方案可避免镦粗失稳缺陷的产生。工艺试验表明,试验结果与数值模拟结果一致。数值模拟结果对工艺试验有一定的指导意义。

Aiming at the problem that large ratio of height to diameter boss appears easily the plastic instability in the process of cold upsetting, the new scheme was worked out which neck firstly and cold upset finally, The necking and cold upsetting process were simulated by Deform-3D software,and then the effects of the diameter of blank and the entering angles of die on forming quality and the plastic force were analyzed. The simulated results show that the new scheme can avoid the phenomenon of upsetting instability. Technology tests show that testing results are in accordance with the simulation. And the simulation results are helpful to process test.