High Strength Steel Automotive Structure Crashworthiness Performance Analysis Considering The Effect Of Stamping History

In the automotive panel stamping process, the rule of sheet metal forming is complicated and difficult to be analyzed because of the complex automotive panel structure and various forming parameters affecting the stamping process of automotive panel. With the development of the computer technology, now CAE analysis is widely used in the automotive industry, which can predict the forming failure like crack and wrinkle.On the other hand, sheet forming processes change the material properties. Although forming histories should be taken into account as the initial condition in the structural performance simulation, in most cases, the effect of forming is ignored. This paper proposes a method to transfer the metal forming simulation parameters (effective plastic strain distribution, thickness, etc.) into the structural performance simulation.In this paper the dynamic non-linear explicit finite element theory is investigated systematically, which includes material models, element algorithm and contact algorithm etc. The finite element methods of stamping and springback simulation are developed and a deep research regarding the selection of parameters is studied. Also, the methods of structural performance analysis considering the forming history are put forward. Based on that, 3 types of DP780 S-shaped stamped parts are used as the analytical models. Forming and springback simulation are conducted and the impact of binder force and friction condition on the forming performance are studied. The crashworthiness analysis is performed, and the impact of forming history, strain rate effect and velocity on the crashworthiness performance of the structure is analyzed.The results show that the forming history have great impact on the crashworthiness performance of the structure, therefore, the forming history should be considered in the integrated forming and performance analysis.