Investigation Of Axial Crashworthiness For Multi-cell Hybrid Aluminum-CFRP Composite Tube

At the present stage,automobiles are the preferred means of transportation for people,and their global holdings continue to grow.As a civilian vehicle,the design goal of the vehicle is to satisfy safety and comfort.In the early days,in order to improve safety,by increasing the vehicle’s ride quality design method,the fuel consumption rate was undoubtedly increased,the emissions of tail gas were increased,and environmental issues became increasingly serious.Solving the irreconcilable contradiction between the two is the focus and difficulty of today’s lightweight design.Lightweight cars mainly start with new materials,new processes,new structures,and new equipment.Carbon fiber-reinforced composite materials have excellent axial strength and modulus as well as good energy absorption properties.They are ideal vehicle crash materials.In addition,the thin-walled beam structure has excellent gradual shrinkage characteristics in the crushing process,and is currently widely used in energy absorbing components such as front longitudinal beams and energy absorption boxes of automobiles.Based on the excellent energy-absorbing characteristics of the new material of the outer-wrapped metal thin-walled aluminum tube and the embedded multi-cell carbon fiber tube,this paper proposes a new structure of the CFRP multi-cell carbon fiber composite reinforced thin-walled aluminum tube,which is absorbed by simulation and test.The energy characteristics were further studied.First,the geometric structure of the new structure and its characteristics are introduced.According to ASTM industry guidelines,the performance parameters of carbon fiber reinforced composites were determined to provide for subsequent simulations.The basic structure test of the thin-walled aluminum tube was performed,and the heat treatment was performed based on the experimental results to better conform to the experiment of the material configuration and simulation requirements.This part of the work can be a preliminary analysis of the failure mode of carbon fiber under different load conditions,and the progressive crush failure mode of the thin-walled aluminum tube under the conditions of the aspect ratio and the thickness-to-diameter ratio.Then,a carbon fiber multicellular aluminum composite structural member was designed to prepare a sample and a quasi-static axial crush test was performed.The axial crushing process was analyzed for a variety of different structures,combined with progressive collapse patterns and load-displacement curves.Based on the characteristics of composite fiber materials as well as the experimental results,the mutual influence and effect of the two are analyzed.The evaluation indexes of energy absorption characteristics such as peak force,energy absorption,specific energy absorption,and collision force efficiency were introduced to analyze the energy absorption characteristics of composite components with different structural configurations,and the conclusions were drawn.Finally,based on the finite element simulation software to fill in the material card,select the Chang-Chang failure criteria,and establish a variety of different structural configurations of multi-cell carbon fiber composite aluminum tube simulation model.The reliability of the finite element simulation was compared with the validation test and the simulation.Combining finite element simulation and experimental research,the law of axial crushing performance of carbon fiber multicellular composite thin-wall aluminum pipe members under the influence of size factors and structural factors was summarized.