汽车铝合金前防撞梁截面的有限空间优化设计

Finite space optimization design of vehicle aluminum alloy front anti-collision beam section

通过准静态拉伸实验获得了某在产中期改款车型材料的应力-应变曲线,在原钢制前横梁的设计空间内开展了铝合金前防撞梁的截面设计及评价。结果表明,正六边形和正八边形截面吸能盒具有较高的稳定承载能力,各边依次同时外凸或内凹,呈逐层叠缩的手风琴压溃模式;正八边形截面吸能盒的比吸能最大,且压溃过程最为平稳和紧凑。综合考虑压溃模式、压溃力演变和比吸能,正八边形截面吸能盒的性能最优。在原钢制前横梁截面的设计空间内,目字形截面的三点弯曲刚度高于田字形截面,但田字形截面前横梁台车系统的比侵入量、比支反力和比吸能均优于目字形截面前横梁。基于此,提出一种铝合金吸能盒和前横梁的截面高效设计和评价方法,为在产车型结构的高效设计提供方法和理论支撑。

The stress-strain curves of materials of a mid-production remodeled vehicle were obtained by quasi-static tensile experiments,and the design and evaluation of sections were carried out for the aluminum alloy front anti-collision beam in the design space of the original steel front beam.The results show that the energy absorbing boxes with regular hexagon and regular octagonal sections have higher stable load capacity,and each side is convex or concave in turn,resulting in crushing in a cascading concertina mode.The energy absorbing box with regular octagonal section exhibits the highest specific energy absorption,and the most stable and compact crushing process.Considering the crushing mode,crushing force evolution and specific energy absorption comprehensively,the performance of the energy absorbing box with regular octagonal section is the best.In the design space of the original steel front beam sections,the three-point bending stiffness with the 目-shaped section is higher than that of the 田-shaped section.However,the specific intrusion,specific reaction force and specific energy absorption of the sled system front beam with 田-shaped section are better than those of front beam with 目-shaped section.Based on this,an efficient design and evaluation method for the section of aluminum alloy energy absorption box and front beam was proposed,which can provide method and theoretical supports for the efficient design of structures of vehicle in production.