凸模圆角半径对不同高强钢板弯曲回弹的影响

Influence of Punch Radius on Springback of Different High Strength Steel

重点研究了凸模圆角半径对高强钢板回弹的影响。通过对厚度为5 mm的FB780和厚度为1 mm的DP780两种强度相似的材料进行V弯的有限元分析和试验研究,分析不同凸模圆角半径对高强度薄钢板以及高强度中厚钢板弯曲回弹的影响规律。研究结果表明:高强度中厚钢板和薄钢板一样,其弯曲回弹角随着凸模圆角半径的增大而增大,但是回弹角大小和方向不同;1mm厚的DP780的试验值和有限元分析值在回弹规律上取得了很好的吻合;对于5mm厚的FB780来说,其90°V弯试验后断面伴随着开裂,而1mm的DP780并没有开裂。

This article focused on the influence of punch radius on high strength steel.By means of V-bending FEM analysis and tests of 5mm FB780 and 1mm DP780,we analyzed the influence rules of punch radius on springback of high strength steel and mid-thickness high strength steel.The research finds out that the springback of the mid-thickness high strength steel increases as the punch radius increases,which is the same as sheet steel,but the springback angles and direction between these two materials are not the same;the results of test agree with results of FEM analysis on DP780.After the 90°V-bending of 5mm FB780,fracture occurs which doesn＇t happen on 1mm DP780.