Design And Optimization Of Hot Stamping B-pillars With Tailored Rolled Blank

With the rapid growth of automobile production and possession,environmental degradation and energy shortage are becoming more and more serious,and the demand for lightweight vehicles is becoming more and more urgent.The thickness of the parts can be designed according to the load-bearing performance requirements of the parts by using the tailor rolled blank,thereby achieving weight reduction.The B-pillar is a typical automotive side safety component that protects the safety of passengers in the car when side impacts occur.Applying the technology of tailor rolled blank to the B-pillar allows it to be safe while maintaining weight.In this paper,the design and optimization of hot stamping B-pillar with tailor rolled blank are studied.The quasi-static crushing and impact collision research of the B-pillar was carried out with the top-hat structures,and the numerical simulation and experiment of the quasi-static crushing of the top-hat structures and the numerical simulation of the impact collision of the top-hat structures were carried out.In the course of the study,the effects of hot stamping information,the effect of the length ratio and the effect of the thickness ratio were considered,and the performance of the top-hat structures of unequal thickness and the top-hat structures of equal thickness were compared under the same weight.Conclusion as below:the deformation of the quasi-static crush model considering the forming information is closer to the actual working condition.As the thickness ratio increases,the crush resistance and collision performance of the top-hat structures are significantly improved,but when the thickness ratio is too large,the deformation mode of top-hat structures is changed.As the length ratio increases,the crush resistance and collision performance of the top-hat structures increase first and then stabilize.With the change of thickness ratio and length ratio,the crush resistance and collision performance of the top-hat structures considering the forming information are reduced by 1%to 10%,but the performance change trend is basically consistent with the shape information.Under the same weight,the unequal-thick top-hat structures are more excellent in crush resistance and collision performance than the equal-thick top-hat structures.A simplified finite element model for the side collision of a B-pillar of a certain type of vehicle is established.Apply the technology of tailor rolled blank to the outer panel of the Bpillar and optimize it for lightweight and crashworthiness.The optimization results are as follows:the optimized mass of the B-pillar outer panel based on the lightweight target is 3.52kg,and the weight loss is 18.7%.Based on the collision performance target,the intrusion amount of the inner position of the B-pillar is reduced by 9.03 mm,the intrusion speed is reduced by 0.73 m/s,the intrusion amount at the position two is reduced by 8.1 mm,and the intrusion speed is decreased by 0.2 m/s.