Study On Local Compression And Energy Absorption Properties Of Aluminum Foam Sandwich Panels

AFS panels,because of a large number of cells in aluminum foam core,can produce a wide range of plastic deformation and absorb plenty of energy under the large impact loading.However,in practical application,connectivity technology between AFS panels and other panels has some deficiencies.The stress concentration and flexibility of the junctions can significantly impact local or whole performances.So,the connection problem of AFS panels is an important topic and the strength and stiffness of the junctions need to be improved reasonably.Before the connection with other panels,AFS panels need to be thinned and compacted locally in one end of AFS panels in order to meet the requirements of connection.Base of above the reasons,local compression properties of AFS panels are systematically studied.The detailed research contents are as follow:Firstly,based on ideal hypothesis of foaming process,three kinds of two-dimensional random models and one kind of three-dimensional random model are created through using C++ and ANSYS/LS-DYNA software.The models of AFS panels can been generated through adjusting length,width,porosity,and other parameters through the generation interface of models.Secondly,based on two-dimensional random models,the research on compression behavior of AFS panels is carried out under different loading rates though using ANSYS/LS-DYNA software.During the quasi-static compression process,The thin cell walls of AFS panels produce plastic deformation firstly,while cells at the top of the models produce large deformation and local densification under high loading rate.Under dynamic loading rate,stress strain curves at the bottom of AFS panels have a certain delay,and with the increase of loading rate,delayed time increases.In addition,the effect of cell radius,porosity,loading rate and the thickness of aluminum foam core on energy absorption capability of AFS panels is systematically studied by using orthogonal experiment,range analysis and variance analysis on base of two-dimensional random models.The research results showed that the influence degree of four variables on the energy absorption property of AFS panels is porosity P>cell radius R>loading rate V>thickness of aluminum foam core H.Moreover,absorbed energy of AFS panels gradually decreases with the increase of the porosity or cell radius,whereas increases gradually under a higher loading rate.The thickness of aluminum foam core has a little effect for energy absorption property of AFS panels.Finally,quasi-static local compression properties of AFS panels with different diameters and porosities are investigated through using electron universal testing machines,respectively.The load-bearing capacity of AFS panels is inversely proportional to cell radius or porosity,that is the,load-bearing capacity gradually decreases with the increase of cell radius or porosity.Due to matrix materials of AFS panels are aluminum-silicon alloy,stress-strain curves of AFS panels have large fluctuations.The stress-strain curves of experiment are basically consistent with the results of the simulation through the comparison and analysis,which confirm the validity of experimental results and the feasibility of numerical simulation.