Finite Element Simulation Of Aluminum Foam And Crashworthiness Research Of Vehicle With B-pillar Filled With Aluminum Foam

Aluminum foam has the characteristics of both foam and metal materials. As acushion filler material with good energy-absorbing propertity, it is increasingly usedin vehicle body structure design to improve passenger car crash safety performance.The vehicle side impact is one of the most common types of fatal crash accidents.Improving vehicle side crashworthiness has always been an important subject.Therefore, considering a unique mechanical property of the aluminum foam with awide platform of compression stress, therefore it is practical and significant to fillthe aluminum foam into the vehicle B pillar for improving vehicle sidecrashworthiness.Firstly，the necessary simplification was suggested according to the complicatedstructure of aluminum foam material. It is assumed that the aluminum foam holesdistributed evenly and regularly. Thus the body-centered cubic and face-centeredcubic unit cell structure was selected as an object of study. Using the DYNA3Dprogram a finite element model is established for simulation of aluminum foam staticcompression. The material properties of aluminum foam were defined based on theavailable data. Through the output from simulation the relationship between the forceand deformation was determined, and the simulation compressive stress-strain curveis drawn and compared with the actual curve from test. The results show that the finiteelement simulation of aluminum foam method in this paper is feasible.Afterwards, a simplified model of the front rail impact is established, in whichrigid wall impacted the front rail at initial velocity of xx km/h. The comparativeanalysis was conducted via simulations of front rail impacts with and without fillingaluminum foam. At the same time, a parameter analysis was carried out in terms of thelength of filling foam and base-material. The results show that the front rail’sdeformation is97mm smaller with filling aluminum foam and the energy absorption islarger. With the increase of filling length, there will be a corresponding increase inenergy absorption by12%.The harder of filling base-material, the higher the front railabsorbs collision energy. However, the factor of harder base-material causes thecollision acceleration increasing. Finally, aluminum foam is filled in the vehicle B-pillar instead of B-pillarreinforcement plate, in order to exam its crashworthiness in side impact. The amountof B-pillar intrusion and intrusion speed were selected as the evaluation values and acomparative analysis was conducted for the energy absorption between aluminumfoam and B-pillar reinforcement plates. The result shows that B-pillar intrusionquantity and intrusion speed have an average reduction of9.8%in the case with filledaluminum foam. Aluminum foam plastic deformation and bending deformation canabsorb energy1.51kJ， which is3times of the energy absorbing by B-pillarreinforcement plate. It is a useful method to improve vehicle crashworthiness in sideimpact by filling B-pillar with aluminum foam.This paper studies the feasibility of finite element simulation of aluminum foam,and focuses on exploring the energy-absorbing of filling vehicle parts with aluminumfoam. It is concluded that filling B-pillar with aluminum foam can improve vehiclecrashworthiness, which provides a reference for vehicle safety design.