점용접부의 동적 파단을 고려한 차체용 부재의 충돌해석

Abstract

In order to get more effective and precise simulation results on the crash analyses of auto-body components, it is needed to adopt the dynamic material properties and the history of fabrication. A resistance spot weld in general finite element models is described as a rigid beam without failure model of a spot weld at the location of the weld. For more accurate crash analyses, not only the dynamic material properties and the forming effect of each auto-body component but also an appropriate description method of a spot weld in the finite element model and the dynamic failure model of a spot weld should be considered in the crash analyses. In this paper, the numerical simulation is carried out considering the dynamic material properties, forming effect of each auto-body component, and the dynamic failure model of a spot weld. A resistance spot weld is characterized as a beam element connecting two shell elements of each sheet at the location of the weld. Comparison between physical crash tests of the front side member and crash analyses is investigated. This study performed is to examine the effect of physical material properties, the fabrication history, and the assembly method on the crash analyses results such as the reaction force, the crushing distance and the deformed shape of auto-body components. The analysis results demonstrate that the accurate prediction of crash analyses results on the front side member is achieved.