Study On Mechanical Properties Of Aluminum Foam Based On Elliptic Random Pore Model

The development of new and reliable building materials is the inevitable trend of the development of architecture and civil engineering.Aluminum foam has become a new type of structural material because of its characteristics such as light weight,high strength,low thermal conductivity,heat resistance,energy absorption and sound absorption.In this paper,an elliptic random pore model was established by designing a FORTRAN language self-compiled program and using ANSYS/LS-DYNA software to simulate uniaxial compression and tensile tests of aluminum foam under quasi-static and dynamic conditions.The effects of porosity,strain rate(10s-1?100s-1)and matrix properties on the compressive and tensile mechanical properties of aluminum foam were analyzed.The energy absorption characteristics of aluminum foam were studied,and the simulation results were compared with the experimental results in the existing literature to verify the validity of the elliptic random pore model,which provides a theoretical basis for the research and application of aluminum foam.Specific findings include:The effects of porosity and matrix properties on the compressive and tensile mechanical properties of aluminum foams with different porosity were studied by quasi-static compression and tensile simulation.The results show that with the increase of porosity,the elastic modulus and yield strength of aluminum foam decrease,and the tensile strength decreases.The tensile strength of aluminum foams with the same porosity is lower than the compressive strength.The yield strength and tensile strength of foamed silicon aluminum alloy are higher than those of pure aluminum alloy.The effect of strain rate(10s-1?100s-1)on the mechanical properties of aluminum foams was studied by dynamic compression and tensile simulation.The results show that the strain rate sensitivity of aluminum foam in dynamic compression simulation is 3.5%and 0.8%,respectively.The strain rate sensitivity of aluminum foam in dynamic tensile simulation is 0.62%and 2.85%,respectively.Therefore,aluminum foam is not sensitive to strain rate in the range of 10s-1?100s-1.The energy absorption properties of aluminum foams were studied.The results show that the energy absorption properties of aluminum foams increase with the increase of the strain variable.Under the same strain condition,the energy absorption of aluminum foams with higher porosity is less.The porosity has little effect on the energy absorption efficiency of aluminum foam.