Effects of Pulse Current on Springback of Cap-Shaped Bending of 1.5-GPa-Grade Low-Carbon Steel
摘要
An electrically assisted cap-shaped bending die has been designed and developed to bend 1500-MPa-grade low-carbon steel obtained by quenching. The influence of the electroplastic effect on the bending process, forming quality, and bending springback of the 1500-MPa high-strength steel was studied by adjusting different electrical pulse parameters and electrification modes. The results show that the pulse current has a significant inhibitory effect on the bending springback of the cap-shaped sheet. Compared with the springback angle of the side wall during cold bending without electricity, the springback angles of cap-shaped bending pieces electrified before bending and after bending are significantly reduced. After electrically assisted bending, the dislocation density and α texture polar density of the sheet decreased, the γ texture polar density in the rounded corner area of the concave mold increased overall, while the γ texture polar density in the rounded corner area and straight wall area of the punch mold decreased overall and tended to be consistent, inhibiting springback to a great extent.