Study On Compression Structure Effect Of Aluminum Foam Sandwich Panels By Finite Element Simulation

The aluminum foam sandwich(AFS)panel is composed of an aluminum foam core and two metal panels,which not only has the characteristics of foam metal,but also increases its strength.The AFS panel is a lightweight structural functional material with high specific strength,sound absorbing and heat insulation,impact resistance,and excellent energy absorption capacity due to the long stress platform in the stress-strain curve.Due to these excellent characteristics,it is widely used in the fields of automobiles,aerospace,construction,and so on.In practical engineering applications,AFS panels are often subjected to local loads and are not loaded as a whole.Therefore,it is important to explore the mechanical properties of AFS panels under local loads.Based on the actual application status,this paper studies the local compression characteristics of AFS panels.The main work contents are as follows:Firstly,the cell inside the AFS panels was simplified.The three-dimensional random ball model was established by Digimat software.The parameters such as size,porosity and aperture can be adjusted through the GUI interface,which is convenient for generating the required model.Secondly,the local compression simulation of AFS panels with different cell shapes(hexahedral model,octahedral model and random spherical model)was performed by Abaqus software.The results show that the cell model is different and the deformation mode of the cell wall is different.For the hexahedral model,the wall instability is the main deformation form;for the octahedral model,the cell wall bending and the plastic hinge are the main degeneration;for the ball model,since the inner wall of the hole has no hole-edge structure,deformation occurs in contact with the other cell wall.Then,the local compressive simulation of the AFS panels was carried out to study the effects of material composition(panel material,panel thickness and matrix material)and structural parameters(porosity and pore size)on its local compression mechanical properties and energy absorption.Porosity,pore size,panel material,panel thickness and matrix material all have an effect on the local compression mechanical properties and energy absorption properties of the AFS panels.Finally,the local compression experiment of AFS panels was carried out by electronic universal testing machine.The effect of core thickness on the local compression mechanical properties and energy absorption of AFS panels was discussed.The increase of core thickness caused the bearing capacity and energy absorption to decrease.Through the comparison and analysis of the experimental and simulation results,the two stress-strain curves are generally consistent in the change trend,verifying the feasibility of the simulation and the correctness of the simulation model.It has also been found that the two differ in the elastic zone,which was influenced by various factors(pressurization process,sample structure characteristics and function of using the software).This provides directionality for subsequent research.The following work in our study team will continue to study the above mentioned differences.