轻质板材平底无铆连接成形模具的优化

Optimization on flat-connecting die without rivet for lightweight material

相较于传统无铆连接,平底无铆连接的主要优势在于通过模具参数设计,避免接头在连接过程中形成凸起,保证接头一侧光滑平整,扩大其在汽车轻量化中的应用。平底无铆连接模具的几何参数主要包括冲头圆角、冲头拔模斜度、压边圈内半径、压边圈圆角和冲压速度。采用正交试验的方法优化了连接模具的几何参数,并通过试验连接板材Al5052对正交试验的结果进行验证。研究结果表明:冲头圆角对互锁值的影响最大,压边圈内半径次之,其次分别是冲头速度、拔模斜度和压边圈圆角半径。在优化的连接模具组合下,对有限元分析和试验结果进行了对比,互锁值的误差为6.1%,颈厚值的误差为8.2%,表明了利用正交试验得到的连接模具可以精确预测平底无铆连接成形过程。

Compared with the conventional connection without rivet,the flat-connecting without rivet has main advantages of avoiding the bump formation visibly during the connecting process,ensuring smooth at the connector and enlarging the application field in the automotive lightweight by die parameter design. The geometrical parameters of flat-connecting die without rivet include punch corner radius,draft angle of the punch,blank holder corner radius,blank holder radius and punch velocity. The above parameters were optimized by the orthogonal design method,and the experimental results were verified by connecting aluminum alloy 5052. The simulation results show that the punch corner radius has a great influence on interlocking value,and followed by blank holder corner radius,punch velocity,draft angle of the punch,blank holder radius. Under the optimum combination of connecting die,the simulation result is compared with the experimental result,and the error of interlocking value is up to 6. 1% as well as the error of neck thickness is 8. 2%. Thus,the connecting die obtained by the orthogonal test can accurately predict the process of flat-connecting without rivet.