变压边力条件下TRIP钢板成形窗口的数值模拟

为提高TRIP高强度钢板的成形质量,提出通过改变刚性凸模胀形试样宽度来测定板料FLC,并对其进行优选。在此基础上,以盒形件为例,借助数值模拟研究其压边力成形窗口以及最优的压边力变化曲线。结果表明:随着冲头行程的逐步增加,TRIP钢板盒形件的压边力成形窗口高度逐渐减小,成形后期必须严格控制压边力的大小;当采用最优压边力变化曲线时,盒形件成形质量好、变形充分。

Numerical simulation on forming window of TRIP steel sheet at variable blank-holder force

In order to improve the forming quality of TRIP high strength steel sheet,the method was proposed to measure the forming limit curve(FLC)of sheet by changing the width of rigid punch bulging specimen,and specimen width was optimized. On this basis,the BHF forming window was established and the BHF curve was optimized with box-shaped workpiece by numerical simulation. The results show that the height of BHF forming window will be decreased with the gradual increase of punch stroke,which indicates that the BHF should be controlled strictly in the last period of forming process. With optimal BHF curve,good forming quality of the box-shaped workpiece is achieved and it deforms adequately.