Study On Dynamic Mechanical Properties And Energy Absorption Performance Of Aluminum Matrix Composite Foam-filled Circular Tube Under Impact

After the incident of 911,the explosion and shock resistance of the civil buildings and large public buildings gradually has been paid widespread attention in the field of civil engineering.thin-walled metal tube and metal foam filled tube,as the most common energy absorbing structures in engineering field,are widely used in the collision energy dissipation system of engineering structures.With the development of material science,domestic and foreign scholars used fly ash and aluminum prepared an aluminum matrix composite foam material with pressure infiltration method,this material has a higher yield strength and wider plastic platform compared to conventional metal foam and demonstrate greater energy absorption properties.Predictably,If we combine this kind of new material,conventional metal foam,and thin-walled metal tube together to create an aluminum matrix composite foam-filled tube,it can have higher bearing capacity and energy absorption properties and the ability to serve in the extreme loading condition of explosion shock and collision impact.In this paper,three kinds of aluminum matrix composite foam whose average particle diameter are 150?m,200?m and 300?m were made into aluminum matrix composite foam-filled tube with 6063 aluminum tubes.Its dynamic mechanical properties and energy absorption under axial impact and transversal impact were studied,the specific contents are as follows:(1)Drop hammer impact testing machine was used to test three kinds of aluminum matrix composite foam-filled tube's axial impact performance.The indicators which evaluate the mechanical properties and energy absorption performance were given.The type of the core,diameter-thickness ratio and impact velocity's effects to specimen's deformation failure mechanism,mechanical properties and energy absorption properties were studied.The mechanical properties and energy absorption properties of aluminum matrix composite foam-filled tubes under static compression and impact are compared and analyzed.(2)Drop hammer impact testing machine was used to test aluminum matrix composite foam-filled tube's transversal impact performance.The type of the core,diameter-thickness ratio and impact velocity's effects to specimen's deformation failure mechanism,mechanical properties and energy absorption properties were studied.(3)The failure characteristics of hollow microspheres in aluminum matrix composite foam and filled tube specimens were observed by optical microscope,and the mechanism of meso failure in the material was analyzed.(4)Using finite element software LS-DYNA to simulate the drop hammer axial impact and transversal impact experiment,the correctness of simulation result is verified through comparative analyses.The finite element simulation model is used to enlarge the experiment parameters and the influence of the thickness to the peak force? average compressive force and specific energy absorption was studied.