Experimental Study On Mechanical Properties Of Aluminum Foam/Polyurethane Composite Wall

Aluminum foam is a lightweight porous material with aluminum and aluminum alloy as its skeleton and contains large numbers of holes.The special spatial structure characteristics of aluminum foam make it have both metal and bubble characteristics.Aluminum foam has excellent cushioning and energy absorbing properties,and it is an emerging material that has been developed and widely used in recent years.By filling the polyurethane viscoelastic material into the hole of the aluminum foam,the structure-functional integrated material with better performance can be obtained,which widens the application range of the aluminum foam in the field of shock absorption,and provides a novice section for the vibration control of the civil engineering structure.The main research in this paper is as follows:In this paper,the compressive and tensile mechanical properties of aluminum foam and aluminum foam / polyurethane composites were investigated by experimental research and numerical fitting.A new type of wall component made of aluminum foam and aluminum foam / polyurethane composites was proposed.And in order to explore the feasibility of its application in the field of structural vibration control,relevant experiments were conducted.1.Through the monotonic compression loading test of 21 aluminum foam,polyurethane and aluminum foam / polyurethane composites test specimens,the whole process of stress was analyzed.The influence of height-width ratio and porosity on the mechanical properties of the material was investigated by calculating the key characteristic points,characteristic values and comparing the compressive stress-strain curves.At the same time,the compression curves of aluminum foam and aluminum foam / polyurethane composites with different porosity at different height-width ratio were fitted by using the phenomenological constitutive model of foam material proposed by Avalle,and the compression constitutive equations at different height-width ratio were obtained.It provides an important guarantee for predicting the monotonic compression properties of aluminum foam and aluminum foam / polyurethane composites.2.Through the monotonic tensile loading test on 18 aluminum foam and aluminum foam / polyurethane composites test specimens,the tensile stress process of the material was investigated.The influence of porosity and material thickness on the mechanical properties was studied by comparing the tensile stress-strain curves and the key stress characteristics.Meanwhile,the monotonic compression and tensile properties of aluminum foam and aluminum foam / polyurethane composites were compared and analyzed.The relationship between the young's modulus and tensile strength of aluminum foam and aluminum foam / polyurethane composites with the thickness and porosity of the specimens was established and a statistical model for predicting the key mechanical properties of tensile strength was proposed,which provides an important reference for predicting the tensile properties of the materials.3.First,the modal parameters including modal frequency,damping ratio and modal shape of the aluminum foam and the aluminum foam / polyurethane composites walls were measured by hammer hammer method,and the modal parameters of the two walls were compared and analyzed.Then,through the quasi-static test of two walls,the whole process of the wall from the elastic stage to the occurrence of cracks during the loading process was observed.The damage evolution characteristics of the wall are studied,the failure mechanism,hysteretic characteristics and energy dissipation capacity of the walls were analyzed,which provides the foundation for the application of foam material to the field of structural vibration control.