基于数值模拟的极限凸翻边研究

Limitative shrink-flanging for sheet-metal based on numeric simulation

为了提高薄板冲压成形零件的疲劳寿命,将半手工操作的落锤压制(冲压)方法改为高压橡皮成形(静压)方法而进行的工艺研究试验;同时,为高压橡皮半模成形确定最合适的工艺过程设计(CAPP)进行计算机仿真.运用自行开发的静-动力有限元软件分析橡皮成形凸模圆角半径和板料厚度对凸翻边成形极限的影响,并建立预测橡皮成形凸翻边成败的t极限翻边高度Hmax、凸模圆角半径r凸、板料厚度t的关系曲面.根据所得数值模拟的极限凸翻边高度Hmax模与7 7万吨橡皮囊液压机的试验结果Hmax实的对比,吻合很好;数值模拟将凸翻边起皱-压贴的真实过程描述得很清楚,而理论计算结果与物理实验结果有一定的差值.

In order to improve the fatigue life of the stamping of sheet-metal, the hamming is replaced with High Hydraulic Press Rubber Forming(HHPRF), and the most suitable CAPP for HHPRF is determined by using computer simulation. The influence of male-die radii and sheet-metal thickness for HHPRF on Forming Limit of parts with shrink-flanging is simulated by self-developed software with Non-linear Finite Element Analysis(FEA) based on explicit-implicit algorithms, and that relationship surface of limitative height of shrink-flanging, male-die radii, and sheet-metal thickness is built to predict the success or failure of HHPRF. The result of limitative height H_(max模) simulated for the shrink-flanging is proposed which is compared with the result H_(max实) of experiments of Hydraulic-Press-77000t and the consequence is good. Compared with results of the theoretical calculation, the real process of crimping the stretch-flanging is more clearly described with numerical simulation method.