Study On Structure Optimization And Crashworthiness Of Crash Box

The automobile front anti-collision beam system is composed of the crash box and the anti-collision beam,which absorbs the energy in the process of the automobile collision.In the collision,the impact force is transmitted to the crash boxes on both sides evenly by the crossbeam to absorb the energy generated during the collision and avoid the damage of the important parts of the automobile.Based on the traditional cross-section box,the energy absorption and crashworthiness of the box were improved and optimized in this study.(1)The traditional rectangular and circular energy absorption boxes are not stable when crushed.Al6061-T6 aluminum alloy was selected as the research material.On the basis of the traditional rectangular energy absorbing box,the number of section edges of the box is increased when the section circumference is the same.The energy absorption characteristics of the boxes with different section shapes were evaluated by the evaluation indexes of energy absorption characteristics.It is found that when the number of edge of the energy absorbing box is increased,the crushing process of the energy absorbing box is stable and the deformation mode is ideal.In order to further improve the energy absorption characteristics of different sections of energy absorption boxes.In order to improve the energy absorption characteristics,the inner wall of the energy absorption box with different section shapes was added into the multi-cell structure.Increasing the number of energy absorption cells,it is found that the number of energy absorption cells is not the more the better.The absorption characteristics of energy absorption box can be improved by proper cell number.(2)In the design of multicellular structure with different section shapes,the improvement effect of circular section energy absorption box is worse than that of other section shapes.Look for other improvements.Under the condition that the parameters are unchanged,the section thickness,the number of induction slots,the position distribution and the upper and lower section diameter of the circular section of the energy absorption box are changed into a conical structure.It is found that different deformation modes occur with different section thicknesses.Proper section thickness ensures smooth collapse deformation and ideal deformation mode.When the induction groove is set up on the thin-walled structure,the impact load is reduced,the deformation of the structure is more regular,and the stress distribution is more concentrated and uniform.By changing the upper and lower diameters of the circular section of the energy absorption box,it is turned into a cone.The energy absorption characteristics of the energy absorption box can also be improved.(3)Based on bionic design,inspired by the structure of bamboo and lotus leaves and stems.On the basis of the above research,the bamboo structure and the load structure energy absorption box are designed,and the multi-objective optimization is carried out.In the imitation bamboo structure,the distance between inducted slots,the Angle of conical section and the thickness of section are taken as the design variables.The load imitation structure takes the bottom radius of the energy absorbing box,cone Angle and section thickness as design variables,and sets constraints on each variable.The objective function of the absorption box is compression displacement and specific absorption energy.The response surface model was constructed and the multi-objective particle swarm optimization algorithm was used to optimize it.The energy absorption effect and deformation characteristics of the optimized structure were improved.Compression displacement was reduced by 42% and 37.59%,respectively.It can effectively reduce the collision loss of automobile parts and passenger injury,and provide a certain reference for the production and research of this type of structure energy absorption box.