Finite Element Simulation Analysis Of Foamed-aluminum Sandwich Panel Applied To Frame

In recent years there are many who carried out the research about car,in order to reduce the energy consumption,fuel level,to improve the safety of the body.Using new material instead of the traditional material is one popular solution that can reduce vehicle energy consumption.According to the existing research results,we known that foam aluminum is light weight,corrosion resistance,vibration absorption,sound absorption,high specific strength and high specific stiffness.It has been widely used for aerospace,energy absorption and noise reduction.But the mechanical properties and safety performance,which frame is laminated by foamed-aluminum sandwich material,is unknown.Therefore,this article has carried on the exploration research in the light weight application by finite element simulation to the frame which is laminated by foamed-aluminum sandwich panel material.First of all,the paper introduced the properties,preparation methods and application status,that foamed-aluminum material and it's sandwich structure.Then simplified frame model(ignoring the connecting components and stiffeners on the frame),and meshing.And use the function of HyperLaminate,created the sandwich panel property,which laminated by steel and foamed-aluminum.Then assigned the material properties to one of the two finite element model as steel,another assigned as foamed-aluminum and steel sandwich panel.When assigning material properties,the components in the actual frame are divided into four thickness specifications,namely 2.0mm,2.5mm,3.0mm and 3.5mm.Ensure that the thickness of the component in model,which was assigned material properties as steel,is consistent with the actual car.The components in the model of frame which material is foamed-aluminum sandwich composite steel plate,is divided into three layers:upper and lower surfaces are steel and middle is foamed-aluminum.In order to facilitate the subsequent analysis of simulation results,set the upper and lower surfaces of the steel layer thickness are 1mm.The middle foamed-aluminum layer thickness is decided by the components thickness in the actual frame,use the actual component thickness minus the thickness of the upper and lower layers in foamed-aluminum sandwiched material(minus 2mm),for make sure that the total thickness of the composite material is the same as actual frame.So we got four different specifications of material properties in the model,that steel was sandwiched with foamed-aluminum material,namely 0mm,0.5mm,1.0mm and 1.5mm.According to the above,the foamed-aluminum sandwich layer is 0mm,which is equivalent to the steel material which does not have the middle foamed-aluminum.Considering that the material less than 2.0mm is not easy to prepare the foamed-aluminum and steel sandwich material,so just assign it as 2.0mm steel material.Actually,there are only tow components in the frame which thickness is 2.0mm,they are front bumper and fixed transverse frame for oil tank.Simulated by Nastran after two different material models have been modelling.Comparing the Free modal parameter,bending stiffness and torsional stiffness of two models,we know the natural frequency of model,the frame of foamed-aluminum sandwich panle is higher than steel frame.The natural frequency of frame,which assigned as foamed-aluminum and steel sandwich material,could avoid resonating with the body sensitive frequency,the idling engine frequency,also the frequency of running vehicle's frame components too,and the bending stiffness decreases by 24.56%,and the torsional stiffness decreases by 4%,but the weight is reduced by 28.71%.The lightweight effect of the frame is obvious in application if the bending stiffness need not too high.