A New Hybrid Bead with Post-stretching Method to Effectively Control Spring-back for Advanced High Strength Steel

International Deep Drawing Research Group 37th Annual Conference

Jia, Yueqian^1 ; Pu, Chao^1 ; Zhu, Feng^1 ; Schmid, Ken^2 ; Wang, Yu-Wei^1

Advanced Engineering and Applications Laboratory, AK Steel Coporation, Dearborn

MI

48120, United States^1

General Motors Corporation, 30500 Mound Rd, Warren

MI

48092, United States^2

关键词: Advanced high strength steel;    Clamping Force;    Element forming;    Finite element simulations;    Good correlations;    Hybrid Bead;    Stinger Bead;    Stretching process;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/418/1/012101/pdf
DOI  :  10.1088/1757-899X/418/1/012101

来源: IOP

【 摘 要 】

Spring-back issues are critical in stamping procedures for advanced high strength steel. The spring-back can be comprehensively controlled by applying a newly designed hybrid bead to effectuate a post-stretching process in a U-channel part forming. Finite element forming simulation is applied in a cross-section to evaluate and optimize the hybrid bead performance, using DP980. A specific post-stretching die with the optimized hybrid bead was manufactured and applied to demonstrate the performances. Excellent spring-back control and material restricting effect were observed in the stamping results. Both effects of clamping force and post-stretching amount are systematically studied, using 1.2mm DP980 and CP1180 AHSS sheets. Significant tonnage reduction was achieved, comparing to the original stinger bead design. An analytical solution was also applied to predict the same process with good correlation.