Impact Of Stamping Effect On Vehicle Crashworthiness

At present,vehicle safety,energy conservation and environment protection have become three main themes of automotive development,improve the precision of crash simulation is a key index of vehicle passive safety research.Structural parts and covering parts on BIW are most manufactured by stamping forming,thickness variation,residual stress and plastic strain in stamping process will influence on crashworthiness of body structures,while consider stamping effect in collision simulation are usually neglected in early research.In this paper,stamping effect was brought in structures before the crash simulation,combined with the finite element theory of stamping forming and crash simulation,the simulation research were performed on the drop-weight test of rectangular section beam?BIW crash and vehicle frontal crash,in order to acquire the crash model more close to actual situation and more precise.The main research contents and conclusions are as follows:1)The method of how to bring stamping effect into simulation model of vehicle crashworthiness was investigated.The variables of stamping effect were converted into standard format of M01,stamping effect was brought in structures of crash simulation model by PamCrash,the errors were 2%-4 % by contrast the data,the feasibility and accuracy of the mapping method was conformed.2)The impact of stamping effect on crashworthiness of rectangular section beam was studied.By compare the experimental data and the simulation results,deformation of the beam increased due to the reduce of shock resistance caused by thickness variation,and shock resistance increased sharply due to the work hardening caused by plastic strain,but residual stress shew no significant influence on the crashworthiness.The peak value of accelerated speed and contact force increased by 8.5% and 8.6%,made the simulation results more similar to experiment situation while consider stamping effect in collision simulation.3)BIW crash with the velocity of 30 km/h was analyzed,energy absorption increased due to the change of deformation caused by stamping effect,the maximal displacement value of B-pillar on left side decreased by 7%,and the peak value of accelerated speed increased by 16%.4)By compare the experimental data and the simulation results of 100% vehicle frontal crash,the trend of acceleration waveform,peak value and the steady intrusion of front wall became more close to actual situation in numerical value after consider the stamping effect,which was an effective way to realize high-precision crash simulation.