Numerical Simulation Of The Mechanical Properties Of Carbon Nanotubes Reinforced Aluminum Matrix Composites

Aluminum matrix composite material has the advantages of light weight,high specific strength,good fatigue resistance,good toughness,high impact resistance,high temperature resistance,wear resistance and so on.Aluminum matrix composites have received more and more attention.It is a new type of composite material which has been developed rapidly in recent years.It has become an indispensable high performance material in the field of aerospace and other advanced technologies.Carbon nanotubes have good toughness,stable structure,small size and good mechanical properties,which is an ideal reinforcement for metal matrix composites.Therefore,Adding carbon nanotubes into aluminum matrix can improve the mechanical properties of aluminum matrix material.In this paper,based on the continuum theory,the 2024 aluminum alloy matrix reinforced by carbon nanotubes was investigated.The mechanical properties of carbon nanotubes reinforced aluminum matrix composites are calculated by the method of representative volume element according to the theory of continuous medium.The representative volume element is composed of hollow carbon nanotubes randomly distributed in 2024 aluminum alloy matrix.The finite element software ABAQUS is used to analyze the representative volume element model and the effects of the volume fraction of carbon nanotubes,the bending angle of carbon nanotubes and the agglomeration of carbon nanotubes on the elastic modulus,yield stress,poisson's ratio and shear modulus of the composites were investigated.The results show that the volume fraction of carbon nanotubes has a significant effect on the mechanical properties of the composites.With the increase of the volume fraction of carbon nanotubes,the elastic modulus,yield strength and shear strength of the composites are obviously improved.When the volume fraction of carbon nanotubes reaches 5%,the elastic modulus,yield strength and shear modulus of carbon nanotube reinforced aluminum matrix composites respectively reach 154GPa,401 MPa and 57GPa.The calculated results of the composites are respectively increased by 120%,29.4%and 128%compared with the elastic modulus,yield strength and shear strength of the aluminum matrix.With the addition of carbon nanotubes,the mechanical properties of the composites are improved obviously,which shows that the carbon nanotubes have a better effect on the aluminum matrix composites.Compared with the same volume fraction of straight carbon nanotubes,the mechanical properties of composites firstly increase and then the mechanical properties of composites decrease with the increase of carbon nanotube bending angle.The agglomeration effect of carbon nanotubes is disadvantageous to enhance the mechanical properties of the composites.