Comparative Study on Crashworthiness of Automobile B-pillar Made of Six Kinds of High Strength Steel

Meng Qinggang, Hai Chao, Guo Xiaojing

（Technology Research Institute of Bengang Steel Plates Co., Ltd., Benxi 117000） Abstract：in this research, the Movable Deformable Barrier（mdb）model for vehicle side impact is established accurately in the explicit finite element software LS-DYNA, and the side impact process of B-pillar of a vehicle is simulated completely. During the simulation, the B- pillar materials are set to DP590, DP780, MS1180, PHS1500, PHS1500 and PHS2000, and the thickness of steel plate is set to 1.2 mm, 1.5 mm, 1.8 mm, 2.0 mm and 2.5 mm, respectively. After the simulation, the position coordinates of typical B- pillar nodes with different materials and thickness are extracted and compared. The results show that, the maximum displacement and bending mode of B-pillar are closely related to the strength of steel plate. The higher the yield strength of steel plate, the smaller the deformation of B- pillar after side impact, however, the B- pillar made of high- strength thick plate is prone to collapse after collision, which leads to the instability of the part. Considering the factors above, DP780 with thickness of 1.5 mm is the best material for the B-pillar. Key words: B-pillar, High strength steel, Collision, Numerical simulation