Technical Paper
Effect of local ductility on crash performance of automotive structures considering press forming strain in advanced high strength steels
2024-04-09
2024-01-2241
A fundamental study on ductility of high strength steels in crash deformation is carried out to investigate the effect of local ductility of various materials on crash performance considering pre-strain produced by the press forming process. In this study, newly developed 980 MPa-grade QP (quenching and partitioning) steels are investigated to clarify the advantage of crash performance compared to conventional DP (Dual Phase) and TRIP steels. The features of QP steel are higher yield strength and higher local ductility due to the optimized microstructure. Axial crash tests are performed to evaluate the crashworthiness of different types of steel Based on the experimental results, the effect of the local duality of the preceding high-strength steel on the risk of material fracture is discussed. In this paper, a newly bending testing method (orthogonally reverse bending, ORB) is proposed to simulate the fracture during crash deformation considering press forming strain.